Building Services Installations Course

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BUILDING INSTALLATIONS COURSE
BUILDING SERVICE
INSTALLATIONS
BUILDING INSTALLATIONS COURSE
BUILDING INSTALLATIONS
CLASSIFICATION
BUILDING INSTALLATIONS CLASSIFICATION
BY FUNCTION
- Heating installations
- Ventilation and air conditioning installations
- Sanitary (plumbing) installations
- Electrical installations
- Natural gas feed installations
- Refrigeration installations
BUILDING INSTALLATIONS CLASSIFICATION
A) Heating installations
Serve for creating and maintaining a thermal comfort
inside a given space.
B) Ventilation and air conditioning
installations
Have the role of removing the polluted air due to man or
technological processes and keep the temperature and
humidity between given limits.
C) Sanitary installations
Are used in order to ensure the cold and hot water feed of
buildings, as well as collecting and evacuating waste water
and drainage.
BUILDING INSTALLATIONS CLASSIFICATION
D) Electrical installations
Serve the electrical energy feed of buildings.
E) Natural gas feed installations
Have the role off ensuring natural gas feed for consumption equipments in
the buildings .
F) Refrigerating installations
Serve for decreasing and keeping a given space’s temperature at a certain
level, below the natural environment’s temperature.
INDOOR CLIMATE.COMFORT PARAMETERS
COMFORT CONCEPT
• THERMAL COMFORT;
• CHEMICAL AIR COMPOSITION - GENUINE
AIR;
• NOISE LEVEL;
• ESTHETICHAL DEMANDS - FURNITURE,
INTERIOR DECORATIONS, COLOURS.
THERMAL COMFORT
THERMAL COMFORT PARAMETERS
• Indoor air temperature t
i
(
0
C);
• Air velocity v
i
( m/s);
• Medium radiation temperature of space
delimitation elements Ө
mr
(
0
C);
• Air relative humidity ø
i
( %).
THERMAL COMFORT
Optimum values for thermal comfort parameters
• Indoor air temperature t
i
(
0
C);
- SR 1907/2 -1997 - t
i
=20-22
0
C;
- Thermal gradient ≤ 2,5
0
C/m
• Air velocity v
i
( m/s);
- V
i
=0,1 – 0,15 m/s
• Medium radiation temperature of space
delimitation elements Ө
mr
(
0
C);
- Ө
mr
= t
i
- 6
0
C
• Air relative humidity ø
i
( %)
- Ø
i
= 30- 70 ( %) Ø
optimum
= 60 ( %) .
HEATING INSTALLATIONS
HEATING INSTALLATIONS
HEATING INSTALLATIONS
HEATING INSTALLATIONS
CLASSIFICATION
Conventional classifications split heating systems into three
groups as follows :
• LOCAL HEATING SYSTEMS;
• CENTRAL HEATING SYSTEMS;
• GLOBAL HEATING SYSTEMS .
HEATING SYSTEMS CLASSIFICATION
LOCAL HEATING SYSTEMS represent heating systems in
which thermal agent is generates in the same place where it is used,
in other words, in the rooms that need to be heated.
• Stoves made of ceramic ware or metal parts.
• Fireplaces
• Electrical heaters.
3
2
1
CERAMIC STOVES
FIREPLACES
THERMO -FIREPLACE
ELECTRIC HEATERS
HEATING INSTALLATIONS CLASSIFICATION
CENTRAL HEATING SYSTEMS may also be classified as:
• Hot water heating systems;
• Steam heating systems;
• Air heating systems.
HEATING SYSTEMS CLASSIFICATION
A central heating system usually contains:
- heating source;
- distribution network;
- indoor heating installation.
Thermal energy necessary for a building, or a group of buildings
it is obtained in a centralized manner, by a single heating boiler which
represents the heating source.
Heating
source
Distribution network
Interior heating
installation
Central heating system
HEATING SYSTEMS CLASSIFICATION
Hot water heating system may be classified according with
the following criteria:
By the manner the heat transfer towards rooms is made:
• by convection and radiation (static elements
heating);
• by convection (air heating or convectors);
• by radiation (using radiant panels).
Radiator heating system
Air heating
Radiant panels heating system
HEATING SYSTEMS CLASSIFICATION
By the manner in which the hot water circulation is made :
• natural (gravitation);
• forced (pumping).
By the number of pipes that supply the heating equipments:
• double pipes;
• single pipe.
Hot water heating with
pumping circulation
Hot water heating
system with natural
circulation
Double pipes heating
system
Single pipe heating
system
HEATING SYSTEMS CLASSIFICATION
By the type of heating equipments:
• radiators;
• floor convectors;
• registers (horizontal or vertical pipe
radiators);
• curved pipes radiators;
• radiant panels.
HEATING SYSTEMS CLASSIFICATION
By the manner of preparation, distribution and hot water supply :
• systems with centralized preparation,
distribution and network adapters for
apartments (in the case of multi-family house
holds);
• systems with centralized preparation and
distribution but individual network adapters
using thermal modules for each apartment (in
the case of multi-family house holds);
• systems with individual preparation,
distribution and network adapters for
apartments (in the case of multi and single
family house holds).
HEATING SYSTEMS CLASSIFICATION
By the distribution of pipes manner:
• radiant;
• tree structure;
• circular.
Tree structure
HEATING SYSTEMS CLASSIFICATION
By the nature of materials the pipes are made of:
• steel;
• plastic materials.
By functioning and exploitation manner of the installation:
• manual;
• semiautomatic;
• fully automatic.
HEATING SYSTEMS CLASSIFICATION
Steam heating systems may be classified according with
the following criteria:
By steam pressure
• low pressure;
• medium pressure;
• high pressure.
By distribution type
• superior distribution;
• inferior distribution.
HEATING SYSTEMS CLASSIFICATION
By steam circulation manner
• free condensation return;
• forced condensation return.
By condensation pipes type
• dry condensation pipes;
• wet condensation pipes.
HEATING SYSTEMS CLASSIFICATION
Air heating systems may be classified according with the
following criteria:
By the air circulation manner:
• normal circulation (gravitation) ;
• forced circulation (fans).
By fresh air ratio :
• re-circulated;
• fresh;
• mixed.
Air heating with natural (normal) circulation
Air heating with forced circulation
HEATING SYSTEMS CLASSIFICATION
Global heating systems –thermal energy is obtained in the
same time with electrical energy in high power stations and heat
transportation is made using long distance transport networks.
By their means:
• Urban;
• Industrial.
BUILDING INSTALLATIONS COURSE
HEAT LOAD
CALCULATION
BUILDING INSTALLATIONS COURSE
BUILDING INSTALLATIONS COURSE
HEAT LOAD CALCULATION
Heat load for a room, Q, expressed in W, is given by the following
formula:
BUILDING INSTALLATIONS COURSE
i
o c
t
Q
A A
Q Q +


\
|
|
¹
|
+
+ =
100
1 [W];
HEAT LOAD CALCULATION
• Q
t
– thermal flow lost by transmission, considered in a stationary thermal
system, corresponding to the temperature difference between indoor and
outdoor of space delimitation elements [W];
• Q
i
– thermal load necessary for heating the air infiltrated from leaky
windows and doors, or by opening them, from the outdoor conventional
temperature[W];
• Ao – Orientation additional coefficient;
• Ac – Cold surfaces effect compensational coefficient;
BUILDING INSTALLATIONS COURSE
HEAT LOAD CALCULATION
BUILDING INSTALLATIONS COURSE

+

× × × =
s M t
Q
R
e i
A m C Q
'
θ θ
m – thermal mass multiplier for outdoor space delimitating elements;
A – the area of each space delimitating element, determined according with STAS 6472/3
[m
2
];
Өi – indoor conventional temperature according with SR 1907 – 2 [
0
C];
Өe –outdoor surfaces temperature, [oC], which can be one of the following :
outdoor conventional temperature according with the appendix of the present
standard;
indoor conventional temperature for the adjoining rooms according SR 1907-2;
R’- corrected specific thermal resistance for the space delimitating element taken into
consideration ,established according with STAS 6472/3, [m
2
K/W];
Qs- thermal flow lost through ground [W];
C
M
- heat load correction coefficient, depending on specific construction weight.
Thermal flow lost by transmission
HEAT LOAD CALCULATION
Thermal mass multiplier for outdoor space
delimitating elements is given by the
following formula:
m = 1,225 – 0,05 D
D – thermal inertia coefficient for the
space delimitating element according
with STAS 6472/3.
For the space delimitating elements with D>4.5,
we shall consider m = 1 ; for outdoor joinery we
shall consider D = 0,5; for the space
delimitating elements in contact with the
ground as well as the ceilings over not heated
basements we shall consider m = 1
BUILDING INSTALLATIONS COURSE
HEAT LOAD CALCULATION
Thermal flow lost by ground, Qs, [W],
BUILDING INSTALLATIONS COURSE
bcj
bc
j i
s
bc
bc
e i
s
s
M
p
p i
p s
A
R
e
n
A
R n
m
C
R
A Q
θ θ
θ θ
θ θ −
+

+

=
1
BUILDING INSTALLATIONS COURSE
t
int.
(t
i
)
t
ext.
(t
e
)
δ
pard.
λ
pard.
δ
o
λ
o
1m
λ
sol.
S
Q
bc
Q
p
HEAT LOAD CALCULATION
• Ap – Total area including floor and walls situated under the ground level, [m
2
];
• Abc – The area of an 1 m broadband situated along the exterior outline of the surface Ap,
[m
2
];
• Abcj – The area of an 1 m broadband situated along the outline that corresponds to the
neighboring space which measures the temperature qi, [m
2
];
• Rp – Total specific thermal resistance including floor and ground layer between floor and 7
m depth from systematized land, or groundwater layer, [m
2
K/W];
• Rbc – Specific thermal resistance for the outlining band corresponding to heat transfer
through floor and ground towards outdoor air, m
2
K/W];
• Өi – Indoor conventional temperature, [
0
C];
• Өe – Outdoor conventional temperature, [
0
C];
• Өej – Indoor conventional temperature for the joined rooms, [
0
C];
• Өp – The temperature as given by one of the following: whether in the ground, at a 7m
depth from the systematized land, when there is no groundwater, or the groundwater layer,
[
0
C];
• C
M
– Correction multiplier;
• m
S
– Ground thermal mass multiplier;
• n
S
– Correction multiplier that takes into consideration the thermal conductivity of the ground.
BUILDING INSTALLATIONS COURSE
BUILDING INSTALLATIONS COURSE
HEAT LOAD CALCULATION
• Ao –orientation additional coefficient, for the
purpose of differentiating heat load for rooms with diversified
exposure to solar radiations;
• Ac –cold surfaces compensating additional
coefficient, for the purpose of correcting thermal balance of
human body in rooms where space delimitating elements have little
specific resistance, it favors increased heat loss by radiation.
BUILDING INSTALLATIONS COURSE
HEAT LOAD CALCULATION
Orientation additional coefficient, Ao, only affects on the thermal flow
lost by space delimitating elements of rooms with underground walls and can have the
following values:
Orientation N NE E SE S SW W NW
A
o
5 5 0 -5 -5 -5 0 5
BUILDING INSTALLATIONS COURSE
HEAT LOAD CALCULATION
Cold surfaces effect compensation additional coefficient,
Ac, only affects on the thermal flow trough space delimitating elements whose medium
thermal resistance ,Rm, does not overrate 10 m
2
K/W.
BUILDING INSTALLATIONS COURSE
) (
t
M e i t
m
Q
C A
R
θ θ −
=
[m2K/W]
•A
t
– Total room area (meaning the sum of all delimitating surfaces), [m2];
•θ θθ θ
i
, θ θθ θ
e
,C
M
şi Q
t
– have previous definitions .
HEAT LOAD CALCULATION
Thermal charge for heating air infiltrated by leaky
doors or windows, or by opening them, from outdoor to
indoor temperature Qi, is determined as maximum value
between thermal loads Q
i1
and Q
i2
[W], where:
BUILDING INSTALLATIONS COURSE
HEAT LOAD CALCULATION
Q
i1
– Thermal load for heating, from outdoor to indoor
conventional temperature, the air infiltrated by leaky doors
and windows, or by opening them, calculated taking into
consideration the number of air exchanges necessary to
obtain physiological comfort, with the following formula:
BUILDING INSTALLATIONS COURSE
( ) [ ]
|
¹
|

\
|
+ + − × × × × × =
100
1
1
c
u e i p M ao i
A
Q c q V C n Q θ θ
HEAT LOAD CALCULATION
Q
i2
- Thermal load for heating, from outdoor to indoor
conventional temperature, the air infiltrated by leaky doors and
windows, or by opening them, calculated taking into
consideration the conventional wind velocity with the following formula :
BUILDING INSTALLATIONS COURSE
( )


\
|
|
¹
|
+
)
`
¹
¹
´
¦
+
(
¸
(

¸

− =

100
1
3
4
2
c
u e i M i
A
Q iLv E C Q θ θ
HEAT LOAD CALCULATION
• n
ao
– number of air exchanges required for obtaining
physiological comfort;
• c
p
– specific heat at a constant air temperature Өi , [J/KgK];
• ρ – air density at an air temperature of qi , [Kg/m3];
• E –height correction factor;
• Өi şi Өe – have previous definitions;
• i – air infiltration multiplier through backlashes,
• L –length of doors and windows backlashes posed on the
walls exposed to wind, [m];
• v – wind conventional velocity, [m/s];
• Q
u
– thermal load for heating air entered by opening exterior,
[W].
BUILDING INSTALLATIONS COURSE
3
4
|
¹
|

\
|
m
s
mK
W
HEAT LOAD CALCULATION
Thermal load required for heating the air
entered by opening exterior doors from
outdoor to indoor conventional
temperature,Q
u
, is given by the following formula:
Q
u
= 0,36 A
u
n (θ
i
- θ
e
) C
M
, [W];
• Au – total exterior opening doors aria, [m2];
• n – number of openings per hour, based on particularities of
the building;
• θ
i

e
,C
M
– have previous definitions.
BUILDING INSTALLATIONS COURSE
Building Installation
Approximation Heat Load
Calculation
Approximation Heat Load Calculation
For approximation heat load calculation Q ,
calculated using indices take into consideration building
type ( residential or offices ) , by form and dimensions (
levels number , developed area and volume building ),
thermal insulation and climate area building .
Approximation Heat Load Calculation
• Residential buildings calcul relation is:
Q= V∙GN∙ (Ɵ
mi

e
) [W]
• V - Interior building heating volume , [m
3
];
• GN – Overall standartized coefficient of thermal insulation of the building ,
determined according to the number of levels N and the ratio of building
area A and volume V [W/m
3
K];
• Ɵ
mi -
Average interior air temperature [
0
C];
• Ɵ
e -
Outdoor convetional temperature [
0
C];
Approximation Heat Load Calculation
• Other buildings, except residential , calcul relation is:
Q= V∙G
1
∙ (Ɵ
mi

e
) [W]
• G
1
– Effective coefficient of thermal insulation of the building [W/m
3
K];
BUILDING INSTALLATIONS COURSE
Heating elements dimensioning
Heating elements dimensioning
The number and size of heating elements is
determined in such manner that the heat
transferred equals the heat lost, Q, calculated
at rated conditions (au pair).
Heating elements dimensioning
The calculation method has ,for all heating
types, the same theoretical basis, but it differs
by heating elements construction type as
follows :
– Heating elements containing more than one body
parts (pieces) (radiators, SP convectors, CRP panel
convectors, etc.);
– Heating elements having as main feature length
(curved pipes radiators, registers, plinth convectors
etc.);
– Heating units – heating elements with a single
component (convectors).
Heating elements dimensioning
The heating element size, expressed as
appropriate, in number of body parts n(
meters of pipe, or a certain size type for the
elements representing an undivided unit) is
given by the formula :
Q
corp
= kS
n
∆t
med
, [ W ];
Heating elements dimensioning
- k represents transfer heat total multiplier of
heating elements, expressed in [W/m
2
K];
- S is the surface where the heat transfer takes
place ,expressed in m
2
/element, m
2
/m or m
2
/
piece;
- ∆t
med
represents the average temperature
difference between thermal agent and the
room calculating temperature.
Heating elements dimensioning
The average temperature difference for hot
water is given by the following formula :
∆t
med
= [ K sau
0
C];
i r
i d
t t
t t
r d
n
t t



1
Heating elements dimensioning
If the ratio < 1,4
i r
i d
t t
t t


ti
t t
tmed
r d

+
= ∆
2
[ K or
0
C];
Heating elements dimensioning
The calculating method according STAS 1797 – 79 appeals the
concept of nominal unit flow
q
n
= kS∆t
m
expressed in W/element, W/m or W/piece and established in
nominal conditions accepted by international standards ,in
which every heating element is tested :
- room temperature (thermal cell where the testing is made)
t
i
= +20
0
C;
– supply hot water temperature t
d
= +90
0
C;
– return hot water temperature t
r
= +70
0
C;
– steam temperature t
a
= + 100
0
C.
Heating elements dimensioning
Radiators dimensioning
Heating elements dimensioning
According with STAS 1797-79 we determine the
number of components for a radiator ,n, using the
formula:
v h m r c t n
corp
c c c c c c a q
Q
n
⋅ ⋅ ⋅ ⋅ ⋅ ⋅ ⋅
=
Heating elements dimensioning
arepresents the correction multiplier depending on
the number of components of an element, taking
into consideration that q
n
was established for a
radiator with 10 components, and that in a bigger
radiator, the unit flow decreases; the multiplier a is
given by the following formula established
experimentally:
a = 0,94 + 0,6/n
Heating elements dimensioning
q
n
unit nominal thermal power for cast iron
radiators
600/200/2 – 152 W/piece
624/4 - 128 W/piece
218/9 - 124 W/piece
Heating elements dimensioning
c
t-
correction multiplier for using the radiator for another average
temperature difference ∆t
m
than the one established in nominal conditions,
given as follows:
Temp.
thermal ag.
t
t
/ t
r
Inside temperature t
i,
0
C
5 10 12 15 16 18 20 22 25
90/70 1,347 1,228 1,182 1,113 1,090 1,045 1,000 1,956 1,89
Heating elements dimensioning
C
c-
correction multiplier for another heat loss of the thermal
agent, different by the nominal heat loss;
For usual installations, c
c
= 1 same as for steam installations ;
c
r
– correction multiplier based on the connection manner for
hot water supplied radiators, a manner which influences
thermal agent circulation.
Heating elements dimensioning
C
m
- correction multiplier based on the mounting manner of
the radiator, which influences the heat transfer by convection
by favoring or inhibiting the gravitational air circulation and
inhibiting heat transfer by radiation due to screen effect;
C
h
– altitude correction multiplier
013 . 1
8 , 0 2 , 0
p
ch + =
Heating elements dimensioning
C
v
- correction multiplier based on the paint nature which
influences the heat transfer by. It has the value 0,95 for light
oil paints, 1 for dark oil paint and 0,9 for metallic pigment
paints. The use of aluminum bronze paints is not
recommended.
The number of components for a radiator resulted from a
calculation formula is rounded to an integer.
Heating elements dimensioning
Curved pipes radiators and
registers dimensioning
Heating elements dimensioning
It aims determination of pipe length necessary for making the
curved pipe radiator or register. Also using the concept oh
nominal unit flow, q
n
,expressed in W / m it returns:
Q
corp
= l⋅ q
n
[ W]
n
corp
q
Q
l =
[ m]
BUILDING INSTALLATIONS COURSE
Central water
heating systems
Water heating systems
• Heating installation with natural
circulation drawings
• Heating installations with forced
circulation drawings
Water heating systems
Heating installation with natural
circulation drawings
Heating installation with natural circulation
drawings
Water heating installation, double-piped, natural circulation, mixed distribution and
open expansion tank
Heating installation with natural circulation
drawings
C – heating boiler;
B – water exchanger with accumulation;
VED – opened expansion tank;
CA – air discharge pipe;
CPP – waste pipe;
CC – connection pipe;
CSD – safety inlet pipe;
CSI – safety outlet pipe;
1 – distribution inlet pipe;
2 – distribution outlet pipe;
3 – inlet pipe;
4 – outlet pipe ;
5 – inlet valve;
6 – outlet valve;
7 –radiator valve;
8 - radiator;
Ca- air discharge pipe.
Heating installation with natural circulation
drawings
The installation contains:
• heating boiler placed in the basement room,
• tree structured distribution network
• supply pipes for heating equipments.
Heating installation with natural
circulation drawings
• By distribution type of both supply and return (inlet
and outlet) main pipes, heating installation with
natural circulation can have:
– inferior distribution ;
– superior distribution ;
– mixed distribution .
• Most of the heating installation are executed in
double piped systems, meaning they use two supply
pipes for the heating equipments.
Heating installation with natural
circulation drawings
• The main supply and return pipes, as well as the
connection pipes for the heating equipments are
fitted with a slant, so that when the installation is
filled with water the air shall be eliminated through
the opened expansion tank.
Heating installation with natural
circulation drawings
• As far as safety is concerned, this was mostly
accomplished using an open expansion tank.
• Still, there are options for ensuring safety with
an closed expansion tank, but it will be
integrated in a safety system made of safety
valves .
Heating installation with natural circulation
drawings
Water heating installation, double piped, with natural circulation, inferior distribution
and closed expansion tank
Heating installation with natural
circulation drawings
C - heating boiler;
B - water exchanger with accumulation;
VEI - closed expansion tank;
VA - air separator;
R - valve;
SS - safety valve.
Heating installation with natural
circulation drawings
• The opened expansion tank has the role of
taking over the volume variations of the water
due to increased temperature,
– thus maintaining continuous contact of the
installation with the atmosphere and air
separating the installation.
• Feeding of the installation must be executed
in the lower point of the return pipe.
Heating installation with natural
circulation drawings
• For the choice of inferior distribution system there is
the ventilation system at the superior side of the
supply pipe for each pipe where the air is collected
and exhausted through the horizontal pipe
connected to the supply safety pipe.
• In order to avoid unwanted circulating water
between the main pipes, the connection with the
safety pipe is made in a sack.
Heating installation with natural
circulation drawings
• For a superior distribution system, circulation
is more active due to adding the thermal
pressure resulted at cooling the water in the
heating equipment with the thermal pressure
resulted at cooling water both in supply and
return pipes.
Heating installation with natural
circulation drawings
Fuel used for the heating boiler may be one of
the usual ones:
• gas fuel,
• liquid fuel,
• solid fuel.
Heating installation with natural
circulation drawings
• This type of heating systems has the
advantage of a simple steel pipe installation
and cast iron or steel reinforcements. On the
other side, there is de disadvantage of large
diameter pipes, therefore a bigger material
consumption.
Heating installation with natural
circulation drawings
• Heating installations with natural circulation
continue to function in the buildings executed
years ago, but along with the rehabilitation
works they will be replaced with other heating
systems.
Water heating systems
Heating installations with forced
circulation drawings
Heating installations with forced circulation
drawings
• This type of installations have the same structure as the
natural circulation installations, except that on the supply or
return pipe one ore more pumps will be installed.
• More than one pump will be mounted for the purpose of
ensuring good functioning. Forced circulation installation can
be made in single or two-piped systems, and their distribution
can also be inferior, superior or mixed.
• The system offers the advantage of smaller pipe diameters,
comparing to natural circulation installations, and it is highly
recommended for wide surface buildings.
Heating installations with forced
circulation drawings
In the following, we will see drawings of a
water heating installation , double piped,
forced circulation, opened expansion tank and
:
• inferior distribution,
• superior distribution,
• mixed distribution.
• heating installation with closed expansion
tank and safety valve.
Heating installations with forced circulation
drawings
Water installation, double piped, with mixed distribution and opened expansion tank
Heating installations with forced circulation
drawings
C – heating boiler;
P – circulating pump;
B – water exchanger with accumulation;
VED – opened expansion tank;
CA – air discharge pipe;
CPP – waste pipe;
CC – connection pipe;
CSD – safety inlet pipe;
CSI – safety outlet pipe;
1 – distribution inlet pipe;
2 – distribution outlet pipe;
3 – supply column;
4 – return column;
5 – connection inlet pipe;
6 – connection outlet pipe;
7 – radiator valve;
8 - radiator;
Ca- air discharge pipe.
Heating installations with forced circulation
drawings
Water installation with forced circulation, double piped, inferior distribution and closed
expansion tank.
Heating installations with forced circulation
drawings
C – heating boiler;
P – circulation pump;
B – water exchanger with accumulation;
VEI – closed expansion tank;
VA – air separator;
R - valve;
SS – safety valve;
Ca – air discharge pipe .
Heating installations with forced circulation
drawings
• Heating system with forced circulation is also
used in apartment buildings with centralized
heating system.
• For single family house holds, or buildings
with a smaller number of apartments, the
system is used only for old or considered as a
solution for the existing ones.
BUILDING INSTALLATIONS COURSE
Individual system for centralized
heating
Individual system for centralized heating
Centralized individual heating
represents a new concept in heating
installations which combines the
advantages of individual heating with
the performances of collective
(centralized) heating.
Individual system for centralized heating
Components:
• 1. heating source – represented by boiler together with
the thermal agent preparation and distribution equipment.
• 2. primary distribution network – containing the distribution
network placed at the boiler’s level and the supply column
for the thermal-hydraulic modules.
• 3. thermal-hydraulic module – containing measuring,
distribution and metering equipments placed in a niche
related with each apartment.
• 4. secondary distribution network or, the so called,
individual apartment knot– to which heating elements are
connected.
Individual system for centralized heating
I-boiler; II-primary distribution; III-thermal-hydraulic modules; IV-apartment knot
Individual system for centralized heating
I – boiler,
II – primary distribution;
III – hydraulic module;
IV – secondary distribution network (apartment knot);
1 - boiler;
2 - thermal agent circulating pump;
3 - distributor; 4 - collector;
5 - supply pipe for primary;
6 - return pipe for primary distribution;
7 - hydraulic module;
8 - inlet;
9 - outlet;
10 - radiator valve;
11 - air valve;
12 - radiator;
13 - supply distribution pipe for secondary network;
14 - return distribution pipe for secondary;
Individual system for centralized heating
The particularity of centralized individual heating
system is the ability of thermal energy consumption
control for each apartment. Heating consumption
records can be made from a common aria, outdoors,
such as the stair case. This demand is claimed by all
inhabitants of apartment buildings or big residence
assembles, for each wants to pay no more than they
consume, and the centralized individual heating
system is able to do satisfy that . Hence, it results the
option of horizontal distribution, specific for each
apartment.
Individual system for centralized heating
In the following we will enumerate other characteristics of this heating
system:
• the common boiler contains the necessary equipments for thermal agent
and hot water preparation, as long as the distribution;
• the primary distribution network, which is one for the entire building,
makes the connection between heating source and he secondary network
through thermal-hydraulic modules;
• thermal-hydraulic modules have the role of separating consumers and
recording thermal energy consumption;
• secondary distribution network, or apartment knot, can be made in
different constructive variants;
• records of thermal energy consumption, hot as well as cold water can be
made due to water meter and heat meter placed at the level of each
thermal-hydraulic module.
Individual system for centralized heating
Heating boiler
• It represents the source of thermal energy for heating , the
place where it’s prepared and distributed thermal agent for
heating and water warming. In the boiler takes place the
transformation of primary energy (fuel) with help from an
entire assembly of equipments and devices. In the interior of
the boiler take place technological processes for supplying
heat in the buildings installations, consequently heat and hot
water for consumers.
• Taking into consideration the role played by the boiler, it is
absolutely necessary that technical matters should be
considered at it’s conception, such as-equipments,
functioning schemes, working manner and exploitation.
Individual system for centralized heating
Based on thermal power, boilers can be
classified as:
• Micro-boilers with thermal power up to 30
KW;
• Mini-boilers with thermal power between 30
and 50 KW;
• Small boilers with a maximum thermal power
of 300 KW.
Individual system for centralized heating
Factors that influence on the choice of a boiler
are:
• total thermal power, respectively necessary
heat of the source;
• type and power of boiler;
• type of fuel;
• location of the boiler;
• automation level.
Individual system for centralized heating
• Due to the fact that a boiler must ensure heating, as
well as warming the water, based on necessary of
heat one can choose one or two boilers.
• For thermal capacities bigger than 100 KW one will
appreciate the need for more that one boiler, even
one will take into consideration the need for a spare
boiler. Based on the fuel type used, the efficiency of
boilers differ, varying between 90% for liquid or gas
fuel down to 80% for solid fuel.
Individual system for centralized heating
Location of boiler in a building is decided
based on functional and economical criteria,
taking into consideration also the gas exhaust
(evacuation) and fuel supply.
Individual system for centralized heating
Central heating boilers
Central heating boiler have the role of
transforming fuel’s chemical energy in
thermal energy using a burner and also
transmitting that energy to a thermal agent.
Individual system for centralized heating
Based on the nature of thermal agent:
– Water boilers;
– Hot water boiler;
– Steam boilers.
Based on the material they are executed:
– Cast iron boilers;
– Steel boilers;
– Stainless steel boilers.
Individual system for centralized heating
• Based on the fuel used:
– Solid fuel boilers;
– Liquid fuel boilers;
– Gas boilers.
• Based on construction manner:
– Horizontal boilers;
– Vertical boilers;
– Fire-tub boiler;
– Water tub boiler, etc.
Individual system for centralized heating
• By pressure drive:
– Low pressure;
– Medium pressure;
– High pressure.
• By usage domain:
– Central heating boilers;
– Industrial boilers.
Individual system for centralized heating
• Cast iron sectioned boilers are made from elements
assembled by nipples that compose the furnace and the
boiler.
• The material the boiler element is made of is a special type of
cast iron ,eutectic, that ensures a homogenous heat transfer
, avoiding cracking due to thermal pressure and
condensation.
Individual system for centralized heating
Cast iron segment with three way
burned gas circulation
Individual system for centralized heating
1-metal case with thermal insulation
2-boiler body made from cast iron segments
3-automation system Vitotronic 300
4-boiler back-folding door
1 2 3 4
Individual system for centralized heating
digital automation block
Vitotronic
thermal transfer surfaces made of
special gray cast iron
high quality thermal insulation
flame tube made of stainless steel
Individual system for centralized heating
Steel sectioned boilers are made of steel seamless
pipes that form convective thermal transfer surfaces. At
modern models these surfaces are composed from one
seamless pipe pressed in the interior of another one, thus
resulting a better thermal connectivity. Through longitudinal
ribs of the interior pipe the thermal transfer surface increases
2.5 times comparing with that given by a smooth surfaced pipe.
The contact points between the two pipes are proportioned in a
manner that, at the posterior part of the boiler, where burned
gas temperature is no longer high, heat transfer towards the
boiler water decreases, avoiding gas temperature loss below
dew point of the vapors contained.
Individual system for centralized heating
Blast air burner
Automation system
Third gas circulation path with convective
multilayer surfaces
Thermal insulation very efficient
Second circulation path
Wide water walls
Burning room (first circulation path)
Individual system for centralized heating
Condensation boilers are in part of the
stainless steel boilers category. These type of boilers
with heat recovery components, represent a new
concept in what concerns the usage of classical fuel
types.
Thermal efficiency of these boilers is determined
based on inferior calorific power of the fuel, which
doesn’t take account of the latent heat of vapours in
the burned gas. If this calculation is applied, for
condensation boilers, one can obtain a thermal
efficiency bigger than one unit. This aspect might be
avoided if thermal efficiency of all boilers should be
calculated based on superior calorific power.
Individual system for centralized heating
1 – heat exchanger plates for intensifying
heating process; 2 –modular radiant
burner; 3 – digital automation system; 4 –
condensation exhaust pipe; 5 – heat
exchanger for water warming; 6 – two
ways circulation pump; 7 – stainless steel
heat exchanger.
Individual system for centralized heating
MODERN SOLUTIONS FOR BOILERS –
”WALLS” INTEGRATED UNITS
The apartment boiler is an assembly that includes :
• the system of producing thermal agent for heating,
• the system of hot water preparation,
• pumping system,
• expansion system,
• safety system.
Individual system for centralized heating
Apartment boiler are mounted on the wall and can be
classified as follows:
- based on the burning room type:
– with open burning room;
– with closed burning room;
- based on burned gas exhausting mode:
– with natural exhaust gas;
– with forces exhaust gas;
- by hot water hater type:
– with instant preparation – these are made in two variants
:with plate heat exchanger and bi-thermal heat exchanger;
– with water heater exchanger with accumulation.
Individual system for centralized heating
Fig. A presents an apartment boiler with closed burning room and plate
heat exchanger for heating water, characterized by :
– electronic flame control by monitoring thermal agent with
temperature sonde;
– electronic ignition and surveillance using an ionizing electrode;
– ability of pre-setting maximum heating power, an useful option for
small and medium apartments where the heat necessary is smaller
than the heating water necessary;
– stainless steel plate heat exchanger for heating water;
– closed expansion tank and 3 bar safety valve;
– three way valve for thermal agent redirecting towards sanitary heat
exchanger operated by differential pressure created by opening one
consumer;
– thermal agent circulation pump with variable volume;
– stainless steel burner;
Individual system for centralized heating
-automatic by-pass for heating installations (for pump protection whether
with thermostatic valves or-in more complex installations using three way
valves );
-freezing protection thermostat (balanced at 60
0
C);
-gas valve with double shutter which automatically closes when ionization
electrode doesn’t detect the flame;
-safety thermostat (balanced at 100
0
C);
- water absence alarm pressure switch and fan and pump post-circulation
devices ;
- burned gas thermostat and differential pressure switch mounted
between the burning gas inlet and the burned gas outlet;
- supervising functioning,signalizing errors and self diagnose at the
control board level;
- intelligent electronic management system and remote controller.
Individual system for centralized heating
Fig. A Apartment boiler with closed burning room, induced draught
and plate heat exchanger for heating water
One step air blower for alternating current
Efficient heat exchanger resistant for corrosion
Expansion tank
Burning room
Blast air modulating burner for reducing polluting
substances emission
Plate heat exchanger for water heating
Automation with diagnose system
Individual system for centralized heating
Fig. B illustrates the hydro module composed from plate heat
exchanger and circulating pump and Fig. C illustrates the frontal
control panel which, using an optical interface, can be easily
connected with a notebook giving the possibility of
programming via internet , mobile phone, etc and also
facilitating maintenance/repair/service.
Fig. B Hydro module Fig. C Automation panel
Individual system for centralized heating
Fig. D Functional diagram for an
apartment boiler with closed burning
room, induced draught and bithermal
heat exchanger
A – heating inlet; B – hot water inlet; C
– gas inlet; D – water inlet; E – heating
outlet; 1 – bi thermal heat exchanger;
2 – gas modulant valve ; 3 –
temperature sonde; 4 – gas valve;; 5
– supply valve; 6 – safety valve ; 7 -
fusemeter; 8 – water pressure switch;
9 – circulation pump; 10 - burner; 11 –
expansion tank; 12 – differential
pressure switch; 13 - fan; 14 –
automatic air vent ; 15 – safety
thermostat; 16 – hot water
temperature sonde; 17 - by-pass.
Individual system for centralized heating
Most used functional diagram is the one in Fig. E that contains: apartment boiler (wall mounted)
and the apartment distribution network with heating elements and water network.
Fig. E Heating installation diagram for
an apartment
a - fan, b – expansion tank, c - burner, d
– plate heat exchanger, e – thermal
agent circulation pump, f – self diagnose
control panel; 1- distribution supply pipe,
2 – distribution return pipe, 3 – heating
element, 4 – radiator valve, 5 – hot
water pipe, 6 – hot water consumer.
Individual system for centralized heating
In the case of a bigger hot water necessary there is the option of using a
accumulating hot water heater.The water heater has a capacity of 40 to 60
liters and can supply the reduced consumption for a short period of time
without soliciting the boiler. Most of the times the heater is part of the
boiler, but it also can be an independent element. Fig. F presents the
diagram of an apartment boiler with incorporated heater.
Individual system for centralized heating
1) Pressure switch, 2) 3 bar safety
valve, 3) circulating pump, 4) gas
modulating electro valve, 5) 8 liters
closed expansion tank, 6) expansion
tank safety valve, 7) burned gas
chamber, 8) burning gas access
chamber, 9) exhaust burned gas
pipe, 10)supply air pipe, 11)
differential safety pressure switch for
the burned gas exhaust fan, 12)
exhaust fan, 13) air valve, 14) heat
exchange wing, 15) burning room,
16) ceramic insulation, 17) stainless
steel burner, 18) motorized three way
valve, 19) heating circuit hydro meter,
20) manual air valve, 21) magnesium
anode, 22) curve, 23) 60 liters heater
Fig. F Functional diagram of an apartment boiler
with water heater
Individual system for centralized heating
Mounting boilers inside an apartment is executed with regard to
Design and Execution Regulation for gas supplying system I6-98.
As in apartments it is mandatory the use of induced draught burned
gas, Fig. G presents some valid options for it’s connection.
MODERN SOLUTIONS FOR BOILERS –”WALLS”
INTEGRATED UNITS
Fig. G Connection possible options for induced draught boilers.
3 – vertical passing trough roof, 4 – connection through exterior wall, 5 – concentric intake and outlet chimney,
6 – intake separated from outlet gas.
Individual system for centralized heating
BUILDING INSTALLATIONS COURSE
Heating elements
Heating elements
Heating elements are those components of a
heating installation with the role of
transmitting in the room to be heated the
heat released be the thermal agent. Heating
elements transfer heat in two manners: by
convection, trough the air that comes in
contact with its surface and by radiation.
Heating elements
Based on the main characteristic of the two
components, a heating element will be named
convector or radiant. Heating elements can be
grouped as :
– static heating elements, where the convective air
circulation is natural. This group contains radiators,
convector-radiators, and convectors.
– dynamic heating elements, where the air circulation is
activated by mechanical means. This group contains unit
heaters, fan coil units and air heater batteries (heating
coils) of mechanical ventilation systems.
Heating elements
Most used from the static heating elements
group are radiators.
Based on the material they are made of there
are three used types:
cast iron;
steel ;
aluminum.
Heating elements
• Cast iron radiators are the classical
heating elements that use as thermal agent
water heated at maximum 115 degrees and
maximum pressure 6 bars or steam at up to
0.7bar pressure.
• Steel radiators are made from special
iron plates with good properties for cold-
embossing, with high thermal power. They are
produced in two constructive models : a)
panel radiators and b) elements radiators.
Heating elements
Steel radiators: a) panel radiators, b) elements radiators
Heating elements
• Most used are panel radiators characterized by their
high thermal power according to the overall size
surface.
• One radiator contains 1,2 or 3 interior convectors.
One panel is formed from two parallel embossed iron
sheets, where there are created one distributor and
one collector united by vertical channels for thermal
agent circulation.
• Radiators are made by combining these panels and
convectors.
Heating elements
Type 11 – 1 panel with 1 convector;
Type 21 – 2 panels with 1 convector;
Type 22 – 2 panels with 2 convectors;
Type 33 – 3 panels with 3 convectors;
Steel panel radiator, constructive models
Heating elements
• Are made in a diverse range, with heights
between 300 and 900 mm and standard
lengths of: 400, 500, 600, 700, 800, 900, 1000,
1100, 1200, 1300, 1400, 1500, 1600, 1700,
1800, 1900, 2000, 2200, 2400, 2600, 2800 and
3000 mm.
• Radiator’s thermal powers vary based on
constructive type, heights and length.
Heating elements
Excepting models we presented, there are panel steel radiators that offer
practical solutions for narrow spaces. These models have heights between
150 mm up to 2100 mm, widths of 450, 600 and 750 mm.
Heating elements
• A special class of radiators are bathroom radiators user
for small spaces, mounted vertically , with a particular design,
having also a decorative role. They are produced in different
constructive shapes with supplementary elements (metallic
bars, mirrors, different types of supports) in order to offer the
possibility of drying towels and event take the room’s shape
(corner radiators or wall-type radiators). These radiators can
be painted in different colors, or chromate versions.
• Thermal powers for these radiators vary between 500 and
1900 W and their dimension vary between 450 – 750 mm
width and 700 – 1700 mm height.
Heating elements
Decoration steel radiators for bathrooms
Heating elements
Aluminum radiators have particular
properties due to material they are made of and to
improve fabrication technology.
The main qualitative characteristics are design,
high thermal efficiency due to increased thermal
conductivity of aluminum, reduced water content
which diminishes thermal inertia as well as smaller
weight and surface occupied comparing to thermal
power developed.
Heating elements
Aluminum radiators with height between 350 and 800 mm
Heating elements
Constructive, aluminum radiators are available in the range 350, 500,
600, 700, 800 mm which represents the distance between axis. There are
models especially designed to solve the heating problem in rooms where
the surfaces available for radiators mounting are narrow. The respective
radiator’s heights vary between 900 up to 2000 mmand thermal power
takes value from 235 to 437 W / element .
Aluminum radiators with heights between 900 and 2000 mm
Heating elements
Fan coil units
Heating elements
• Heating and air-conditioning were treated as
separate systems. The connection element is
nowadays the fan coil unit (fan coil) which changes
the manner of studying heating and air-conditioning
as a unit.
• Fan coil is a terminal element of a heating and/or
air0conditioning installation which has two basic
components: one heating battery (coil) and a fan.
Heating elements
1. adjustable outlet grille, 2. heating coil, 3. condensation collector,
4. electric fan, 5. air filter, 6. fresh air intake
Heating elements
• Working principle is simple : the outgoing air trough
fan is supplied by heating coil in the room. Generally
the fan coils are mounted under windows and use
the re-circulated air, but there are models that allow
interference of fresh air, or exclusive fresh air supply.
• There are many constructive types: vertical,
horizontal, as well as models designed for hidden
(masked) mounting in walls or false ceilings,
especially in large rooms or if they serve for more
than one room .
Heating elements
Fan coils constructive types
a) vertical, b) horizontal, c) masked mounting models
Heating elements
Fan coils with masked mounting in false
ceiling previously presented can be used for
larger or more than one room. These models
come very close as far as functionality and size
as the inferior limit of one piece air handling
units. Just like these, fan coils use supply and
exhaust ducts, air intakes, air diffusers and
exhaust air holes.
Heating elements
1. fan coil, 2. conditioned air exhaust air, 3. re-circulated supply hole 4. supply
fresh air duct, 5.re-circulated air supply duct, 6. conditioned air exhaust duct
Heating elements
Based on thermal agent used, fan coils allow
heating or cooling the air in a room. We must
stress that fan coil can function for heating as well
as for cooling with the same battery (two pipes fan
coils), or can use two separate batteries (four pipes
fan coils) , leaving the option of choice to the
designing engineer.
As construction features, fan coils can have
accessories as follows:
– speed adjustment (air flow) fan : in steps (at least 2 +
stop) or continuous;
– water flow adjustment with two or three way tap.
Heating elements
Electronic control device for fan coil
Control of air velocity or water flow can be made manually, from the switch, or
tap or automatically. Automatic control supposes the existence of an
thermostat which allows setting the fan on/off and/or shutting the tap.Evolved
systems impose fitting fan coils with a control device that act on the tap of each
battery and on the fan.
BUILDING INSTALLATIONS COURSE
Central heating installations pumps
Central heating installations pumps
Thermal agent’s circulation inside heating
installations is ensured by circulation pumps.
Their role is to overcome linear and local
hydraulic resistance in the most unprivileged
circuit of the heating installation. For small
and medium capacities there are usually used
pipe mounted pumps (in-line
pumps) with variable speed, low electrical
energy consumption, silent and very reliable.
Central heating installations pumps
The main characteristics of a pump are:fluid flow
rate G, expressed in m3 / h and
pressure difference between supply
and exhaust expressed in N /m2 or in
bars. In some cases one uses the notion of :
pumping height H as the equivalent of pump
pressure expressed in liquid column height. It is also
important to know the shaft motor’s power P, in kw,
speed n, supply voltage and electric power
frequency.
Central heating installations pumps
Ccharacteristics of a pump with humid rotor and variable speed
Central heating installations pumps
Circulation pumps must always be chosen in such
manner that the functioning point places on the
characteristic Q/H corresponding to maximum motor
speed, in it’s point ,or closest to maximum efficiency.
Choosing the pump
Central heating installations pumps
Examples of thermal agent circulation pumps
Pumps with humid rotor Pumps with dry rotor
Central heating installations pumps
• Thermal agent flow resulted from calculations can be varied
with more pumps in parallel connection. Parallel mounting is
currently used for the purpose of achieving a flexible
functionality, as well as increased safe exploitation.
• In the case of two identical pumps parallel mounted in the
same network, the common characteristic curve of the two
will be obtained by doubling characteristic flows for a certain
pumping height. It is also possible the parallel mounting for
two pumps with different characteristics, on the condition
that maximum pumping height will be the same. Functioning
point for the two pumps parallel connected is the intersection
point of pumps common characteristic curve with network
characteristic curve.
• Pumps must be chosen in the manner that the functioning
point be positioned in the maximum efficiency aria.
EXPANSION TANKS
EXPANSION TANKS
EXPANSION TANKS
• In any water heating installation may occur dangerous
overpressure situation up to explosion, as consequence of
exceeding vaporization temperature.
• Standard 7132 / 1986 classifies water heating installations
with maximum temperature up to 115
0
C into two categories:
– Installations directly related with the atmosphere, provided with
opened expansion tank;
– Installation not related with the atmosphere, provided with
safety valves and closed expansion tank.
EXPANSION TANKS
• A safety system with opened expansion tank has the
following functions :
• overtaking water volume variations, due to normal
temperature variations heating-cooling and ensuring a water
reserve which covers for reasonable period of time the small,
inevitable loss;
• exhausting in atmosphere the steam resulted as less
supervising the boiler, errors, malpractice, negligence,
automation breakdown, etc.
• maintaining the installation filled, once filled up, up to a level
that exceeds higher consumer’s level, in an inferior
distribution installation, respectively, pipe network level, in
case of a superior distribution installation;
• exhausting air during filling up the installation, as well as
supplying it during emptying it, in the manner that no air nor
water sacs are formed.
EXPANSION TANKS
• For the choice of ensuring heating installations with safety
valves and closed expansion tank, safety systems
functions are satisfied as follows :
• overtaking volume variations and the small water reserve by
the closed expansion tank;
• maintaining at full capacity the water in installation by the
pressure exerted by the air cushion over the water from the
closed expansion tank , which, in this case may be mounted at
the inferior part of the installation, close to the boiler;
• upper limitation of installation pressure using safety valves
mounted on the boiler before every shutting element;
• exhausting air at filling and supplying it at emptying the
installation trough ducts, tanks and air valves.
EXPANSION TANKS
Closed expansion tank is provided with an elastic membrane between eater cushion
and water
Closed expansion tank types
a-rectangular type, useful volume 6-16l
b-disc type, useful volume 6-20l
c- cylinder type, volume 6-300l
1-connection to boiler’s return pipe;
2-tank wall;
3-elastic membrane;
4-water surface with variable volume;
7-support
5-air surface with variable volume
6-compressed air valve
EXPANSION TANKS
• A closed expansion tank is mounted at the inferior
part of the installation, close to the boiler. Upper
limitation of pressure is made using safety valves
mounted on the boiler previous every shutting
element.
• Exhausting air at during filling and supplying air at
exhaustion is made with manual or automatic air
valves.
• Constructively, closed expansion tanks can be
rectangular, disk, or cylinder type, and their volume
vary between 6 up to 5000 liters.
EXPANSION TANKS
Closed expansion tanks
Heat exchangers
Heat exchangers
Heat exchangers
Heat exchangers are units used for hot
water preparation for the option of
accumulation installation (water heater) as
well as without accumulation.Likewise, heat
exchangers are used in heating systems for the
superior parts of high buildings or for heating
buildings part of centralized heating systems
that use hot water or stem as primary agent.
Heat exchangers
Water heaters are heat exchangers with water
accumulation used for hot water preparation and they
are constructed in two shape types: horizontal and
vertical. The heat exchange surface, respectively, the
coil, will be dimensioned in a manner that will ensure
warm water flow in accordance with the temperature
difference from the secondary circuit (+10
0
C cold
water temperature, +60
0
C warm water temperature )
and with the temperature difference from the primary
circuit.
Heat exchangers
Horizontal water heater Vertical water heater
Magnesium anode or external current
anode
Surface completely
thermal insulated
Superior coil
Water heating from boiler
Ceraprotect protection
Inferior coil connected to
solar panel
Cleaning pass
Heat exchangers
• Water heater capacity varies from 80 up to 1000 liters.
• Water heater body is made from anticorrosive protected steel
, and for supplementary cathode protection a magnesium
anode is used, or, optionally an anode fed from an external
source.
• Heat losses are diminished by completely covering the heater
with a thermal insulated layer.As a construction option, water
heaters can performed as bivalent water heaters in systems
with solar panels combined with boilers.Heat supplied by the
solar panel is transferred in the heater trough the inferior coil.
As an option some heaters can be provided with an electrical
heating system.
Heat exchangers
• Besides the types presented above, there is another
constructive model called Tank in Tank
,meaning, stainless steel heaters, with high
resistance to extremely corrosive water without
temperature (fig. 3.26).
• Stainless steel used is a chrome-molybdenum alloy
witch give resistance to all temperatures and
corrosive waters up to 2000 mg chlorides/liter.
• These types of heaters are used for direct sea water
heating, for therapy water, residual water in regions
with extremely corrosive waters, and they are
recommended in industrial applications that use
corrosive waters.
Heat exchangers
Tank in tank heater
1.Steel interior tank DUPLEX DIN 14462
2.Steel exterior tank
3.Rigid polyurethane foam insulation
4.Inlet heating agent (primary)
5.Outlet heating agent (primary)
6.Cold water inlet (secondary)
7.Hot water outlet (secondary)
8.Control thermostat
9.Control thermometer
10.Control thermostat bulb
11.Control thermometer bulb
12.Air valve
13.Metalic coating
14.Hot water recirculation valve
Heat exchangers
Heat exchangers without accumulation.
The most common in this range are plate heat
exchangers. They are simple devices used for
thermal energy transfer between two fluids, made of a
pack of identical stainless steel plates, with sealing,
aligned at the both superior and inferior part of two
supporting pipes between two pressure plates, one of
them fixed and another mobile. The pack is sealed with
sealing guys. Between the plates a free space is left for
fluid circulation; they are kept equidistant from humps,
scratches or dimples.
Heat exchangers
• Each plate has two walls, one representing the front,
the other one the back of the plate.
• Fluid 1 flows all along the front of the plate and
bathes it and fluid 2 flows along the back of the same
plate, in counter-flow with fluid 1: in this manner the
heat is transfer along the entire surface of the plate,
while the gaskets tighten the border of the plate and
in the same time separate the fluids.
Heat exchangers
A plate heat exchanger design
Heat exchangers
• Plate heat exchangers are used in heating for thermal points
modernization, for heating or preparing heated water, in the
heating and cooling processes, in heat recovery, for thermal
tests on fluids (e.g. pasteurization) and in situations were
working fluids are corrosives( using plates executed from
austenitic stainless steel, resistant to corrosives
environments).
• Stainless steel plates are 0,5 – 0,6 mm thick, which allows
achieving a very good transmission coefficient as well as a
reduced thermal emission, but also lead the fluid in the heat
exchanger. They are made of rubber resistant at up to 150
0
C
temperature (propyl-ethylene), silicon rubber or food industry
rubber .
Heat exchangers
Heat exchanger plates
Plate heat exchangers
BUILDING INSTALLATION COURSE
LOW TEMPERATURE RADIATION
HEATING SYSTEMS
Low temperature radiation heating systems
• Radiant floor heating – by including heating
elements inside the floor ;
• Radiant ceiling heating - by including heating
elements inside the ceiling;
• Radiant wall heating – by including heating
elements or radiant panels (opened or closed
radiant panels ) inside the walls.
Low temperature radiation heating systems
Using delimitating elements of a surface as
radiant elements imposes, from
physiological reasons, the limitation of
surface temperatures as follows :
• 40
0
C for ceiling heating;
• 29
0
C for floor heating;
• 70
0
C for walls heating.
Low temperature radiation heating systems
Radiant panel heating systems are system
where the thermal agent conductive pipe or
electric heating wires are buried in the floors
(whether floor, ceiling or walls).
Low temperature radiation heating systems
Low temperature radiation heating, aside the fact that
gives the possibility of using thermal agents with low
parameters, also presents advantages in what thermal
comfort is concerned :
• reduced temperature gradient;
• more uniform temperature repartition over the delimitating
surfaces;
• rising interior temperature at the level of delimitating surfaces
and achieving a better thermal comfort for a room air
temperature with 1 up to 3
0
C smaller than usual, which is an
important comfort factor;
• space saving is made and superior architectural esthetic is
ensured;
• solves the energy problem by giving the chance of cooling
rooms during summer, which is a serious problem as far as
comfort is concerned.
Low temperature radiation heating systems
Reduced temperature on heating surfaces imposed
the use of wider surfaces for heating, a work for
which the delimitating surfaces fitted successfully,
thus obtaining :
• radiant ceiling heating in which case the medium
temperature cannot exceed + 40
0
C ;
• radiant floor (under floor) heating, in which case the
medium temperature is limited at +30
0
C ;
• radiant wall heating, in which case temperature can
reach up to + 70
0
C .
Low temperature radiation heating systems
Radiant floor heating
Low temperature radiation heating systems
Radiant floor heating installations have the
following components:
• the heating floor panel;
• distributors-collectors (which are the common
element of more heating circuits);
• adjustment equipment ;
• thermal energy source.
Low temperature radiation heating systems
A radiant floor panel contains:
• the insulation layer (for thermal and acoustic insulation)
;
• the insulation protection layer ;
• heating pipes ;
• thermal flow allotment and emission slab (heating slab);
• final floor ;
• other elements, such as : diffusion layer, marginal
insulation, etc.
Low temperature radiation heating systems
The temperature at the floor level is limited,
from physiological reasons at up to +30
0
C,
based on the destination of the room.
Low temperature radiation heating systems
A heating floor’s structure
1)Interior coating, 2) plinth, 3) area strap, 4) final surface, 5) mortar layer, 6)
cement layer, 7) heating pipe, 8) covering foil ( PE foil or red rosin paper), 9)
thermal and acoustic insulation layer, 10) hydro insulation, 11) concrete plate,
12)soil.
Low temperature radiation heating systems
Heating system with vario compact naps plate
Low temperature radiation heating systems
sistem cu şine de fixare
Heating system with wire screen
Low temperature radiation heating systems
Heating system with mounting rails
Low temperature radiation heating systems
Low temperature radiation heating systems
Low temperature radiation heating systems
The mounting rails system ensures rising the pipe up to 5mm, and thus a
minimum height for the cement layer. Sustaining clamps and clips
guarantee a solid fixing of the pipe.
Pipe fixing Pipe fixing with clamps and clips
Low temperature radiation heating systems
Wire screen system Rotating clips
Low temperature radiation heating systems
Border insulation
• Before the slab, along the walls, an insulating strap will be laid, around
frames and pillars. Insulation will be laid from the base floor (sub floor) till
the final floor, allowing a maximum displacement of 5 mm.
Low temperature radiation heating systems
Overview for a house-downstairs
Low temperature radiation heating systems
Overview for a home-upstairs
Heating floor system
Low temperature radiation heating systems
Radiant ceiling heating
Low temperature radiation heating systems
This type of heating system allows achieving a
more homogenous air temperature, as well as a
more reduces air circulation, which are considered
important advantages as far as thermal comfort is
concerned.
For the heating surface the hole ceiling is
available ,except for the cases where there are large
windows (glass surface) when supplementary
heating surfaces will be added (for example inside
the exterior walls).
Low temperature radiation heating systems
• Main advantage is given by elimination of
exterior heating elements, thus obtaining
more free space, more architectural freedom.
The space gained, for social buildings, can be
considered an important space saving.
• Another advantage is given by the option of
cooling the ceiling during summer, thus a
reversible ceiling.
Low temperature radiation heating systems
• This system is very reliable in museums, showrooms
or commercial places.
• Due to hygienic advantages, the system is preferred
in hospitals, nursing homes, medical centers.
• The possibility of reversing ceiling heating, meaning
cooling during summer represents a big gain for
choosing this system in administrative and office
buildings.
Electric heating ceiling
Water heating ceiling
Low temperature radiation heating systems
Radiant wall heating
Low temperature radiation heating systems
Transforming walls into heating surfaces by
integrating a curved pipes system, is possible taking
into consideration the following aspects:
• exterior walls require supplementary thermal
insulation;
• there is always the chance of piercing the pipe ,
specially in apartment buildings (e.g. with paintings
supports);
• placement of furniture will restrict the radiant
thermal flow of the walls.
Low temperature radiation heating systems
Radiant wall heating can be used in different
variants :
• individually;
• in combination with radiant floor heating
system;
• in combination with radiators heating system.
Low temperature radiation heating systems
Radiant wall heating variants
Wall heating structure
BUILDING INSTALLATION COURSE
VENTILATION INSTALLATIONS
VENTILATION INSTALLATIONS
VENTILATION SYSTEMS
• NORMAL VENTILATION
• MECHANICAL VENTILATION
VENTILATION INSTALLATIONS
NORMAL VENTILATION
Unorganized normal ventilation systems
ventilation is accomplished by opening doors and
windows, by leaky rooms, offices, warehouses,
working places, etc.
Organized normal ventilation systems
ventilation is made through gaps or special
constructions, windows, scuttles, ventilation
chimneys in kitchens, bathrooms, industrial
buildings,etc.
VENTILATION INSTALLATIONS
MECHANICAL VENTILATION
General mechanical ventilation systems – uses
fans for air circulation that serve the entire building and make the
circulation for the entire air volume in industrial buildings, social,
cultural, commercial, administrative, etc.
Local mechanical ventilation systems act on the air
supply source, sweeps the air around the source, absorbs the
harmful substances before the air comes back in the room (
industrial furnaces, weld tables, industrial zinc bathing, varnish
removals, grinders, wood processing etc.) .
Mixed mechanical ventilation systems – apply
both general and local ventilation.
INSTALATII DE VENTILATIE
Local ventilation with wall outlet and pipe mounted fans
VENTILATION INSTALLATIONS
General ventilation installation with air handling unit
VENTILATION INSTALLATIONS
MECHANICAL VENTILATION SYSTEMS
VENTILATION INSTALLATIONS
MECHANICAL VENTILATION
• SYMPLE – INLET/OUTLET
• MIXED– HEATING / COOLING-DRYING/
HUMIDIFICATION
VENTILATION INSTALLATIONS
By the pressure difference between inside
and outside the ventilated room we have:
• BALANCED VENTILATION–inlet flow
= outlet flow
• OVERPRESSURE VENTILATION–
inlet flow > outlet flow
• DEPRESION VENTILATION–
outlet flow > inlet flow
VENTILATION INSTALLATIONS
VENTILATION INSTALLATION
DRAWINGS
VENTILATION INSTALLATIONS
1. intake
2. collector pipe
3. noxious air exhaust fan
4. protection cap of outlet
noxious air pipe
5. dust filter
6. heating coil
7. warm air force fan
8. pipe network
9. discharge openings
10. heat recuperator
General mechanical ventilation system
VENTILATION INSTALLATIONS
1. intake
2. collector pipe
3. noxious air exhaust fan
4. protection cap of outlet noxious
air pipe
5. dust filter
6. heating coil
7. warm air force fan
8. pipe network
9. discharge openings
10.mixing chamber
VENTILATION INSTALLATIONS
Basic drawings for general ventilation installation
VENTILATION INSTALLATIONS
Basic drawings for an air cooling installation
VENTILATION INSTALLATIONS
Ventilation installation with air dehumidification
VENTILATION INSTALLATIONS
Ventilation installation with air dehumidification without fresh air inlet
VENTILATION INSTALLATIONS
Air handling unit
VENTILATION INSTALLATIONS
COMPONENTS OF A VENTILATION
INSTALLATION
A ventilation installation contains:
– air ventilation unit ;
– duct (pipe) network;
– ventilation grids ;
– regulating devices;
VENTILATION INSTALLATIONS
Air ventilation units
• Air ventilation units are placed in specially
designed places, in the interior or exterior of
buildings
• Air ventilation units introduce fresh air. They
contain modules in which equipments are
mounted.
VENTILATION INSTALLATIONS
Modular air handling unit
VENTILATION INSTALLATIONS
Modular air handling units- components
Air handling units components
• Casing
• Dampers
• Filters
• Heat exchangers (coils)
• Heat recovery devices
• Humidifiers
• Fans and Motors
Casing
• Aluminum frame with rounded corners
• Panels slotting directly into the frame
• No fixing screws
Panels
• 50 mm sandwich panels
• injected polyurethane insulation (42 kg/m3 foam
density) or mineral wool (40 kg/m3 or 100 kg/m3)
• Special executions for fan section extra noise
reduction
• G2 metallic (eff. 75%, EU2)
• G3 (efficiency 85%, EU3)
• G4 (efficiency 90%, EU4)
SYNTHETIC PREFILTERS:
BAG FILTERS
• Rigid or soft bags
• Class F7
• Class F9
Available Filters:
• Absolute filters
• Roll filters
• Carbon filters
• Electrostatic filters
• UV lamps
• Water coils
• DX coils
• Steam coils
• Electric coils
Heat exchangers (coils, batteries):
• Efficiency: 50-70%
• G4 prefilter (fresh air) as standard
• Drain Pan
• Recirculation damper
• By-Pass damper
Plate Heat Exchangers:
• PVC wet deck with/without
recirculating pump
• Paper wet deck with/without
recirculating pump
Adiabatic Humidification:
• Water+Compressed Air
• High Pressured Air
• Air Washer
Steam Humidification
• steam manifold in stainless steel AISI 304
• with or without steam producer
Plug fans:
• Backward-curved blades
• Direct-driven fans
• Very easy to clean
Air handling unit
Chiller
7 -12 C
Boiler
70 -90 C
Air handling unit +chiller + boiler
VENTILATION INSTALLATIONS
Fans
Fans contain :
-chassis with two connection pieces :for air inlet and
outlet
-rotor with blades depending on fan type
-electric engine for rotor actuation
Fans can be :
- centrifugal (radiant )
- axial flow
VENTILATION INSTALLATIONS
Centrifugal fan for circular ducts
VENTILATION INSTALLATIONS
Centrifugal fan for rectangular ducts and silencer mounted in the interior
VENTILATION INSTALLATIONS
Roof centrifugal fans with horizontal or vertical exhaust
VENTILATION INSTALLATIONS
Air filters
Filters know different types:
- Filters with air filter cells .One cell contains a
metallic case filled with metallic perforated foils
impregnated with mineral oil, overlapped. Cells are
placed in a rack.
- Dry band filters .At superior part a coil with synthetic
fiber filter is attached .At the inferior part there is the
coil that rolls the dirty. The material ,which creates a
screen through which the dusty air passes, rolls
between the two coils.
- Self-cleaning filters .Filter is made of cells cleaned in
an oil bath.
VENTILATION INSTALLATIONS
Heating coils
Are made of a wings pipes fascicle in an iron
case with flanges to which ducts are
connected. Trough ducts steam or hot water
flow and between them circulates the air that
heats due to heat transfer by ducts contact.
VENTILATION INSTALLATIONS
Duct coils for heating or cooling (for both rectangular or circular ducts)
VENTILATION INSTALLATIONS
Electric line heaters (for both rectangular or circular ducts)
VENTILATION INSTALLATIONS
Heat recuperators
VENTILATION INSTALLATIONS
a) Wheel heat recovery
Wheel heat recuperator
1. purification sector
2. electric engine
3. metallic case
4. rotor
Fresh
air
Noxious
air
VENTILATION INSTALLATIONS
• The most used is wheel recuperator.
• At the case the ducts for cold and warm air are connected.
• Rotor contains a heat accumulation surface with the looks of a honeycomb
with small channels parallel with the rotation axis. At small speed, the
rotor offers the two air flows ,warm and cold, a heat exchange surface.
Rotor accumulates heat in contact with hot air which the transmits it to
the cold air, after rotating. At the edge of the two flows there is a
purification sector, with clean air for cleaning ducts where noxious air
flows. In order to increase the heat exchange, the rotor’s surface is
covered in a solution containing lithium chlorate, which is an excellent
absorber. Due to this substance rotor also absorbs vapors from the warm
air which it transfers to cold air. Due to lithium chlorate and the fact that
heat accumulation mass comes alternatively in contact with both air
flows, wheel recuperator achieves a total heat transfer, thus resulting in a
high thermal efficiency.
• In order to be mounted in the ventilation systems, wheel recuperators
require a meeting point for the cold and warm air ducts, where heat
exchanger should be mounted.
VENTILATION INSTALLATIONS
b) Intermediate fluid heat recovery
system
1. noxious air duct
2. wings pipes coil
3. fresh air duct
4. circulating pumps
5. ducts
VENTILATION INSTALLATIONS
c) Plate heat recovery
The device is made of parallel plates installed
in a case. Plates are mounted at small
distances, forming narrow, parallel channels
for cold and warm air circulation. Plates are
mounted in manner that allows cold and
warm air an alternative circulation. Heat
transfer is made through plates surfaces.
VENTILATION INSTALLATIONS
FRESH AIR
EXHAUST
AIR
VENTILATION INSTALLATIONS
Prefabricated, small dimension fans with energy recovery mounted in the
interior ( heat reccovery )
VENTILATION INSTALLATIONS
Blinds frames for air chambers
Blinds are mounted in a metallic frame bounded
through articulations at a common lever which
simultaneous actions all blinds. The lever can be
maneuvered manually or using an automatic device
operated actuator.
VENTILATION INSTALLATIONS
Blinds frames simultaneously adjustable
Conjugated blinds frames
VENTILATION INSTALLATIONS
Blinds frames simultaneously adjustable
VENTILATION INSTALLATIONS
VENTILATION PIPES ( DUCTS)
VENTILATION INSTALLATIONS
• Ventilation pipes contain :
– straight ducts
– special pieces : bends, branches, level change pieces,
diffusers ,confusers, etc.
• Used materials :
- black or galvanized sheets;
– plastic materials , mineral fibers plates , etc.
• Ducts shape : circular or rectangular .
• Ducts dimensions ( diameters , sides ) are standard.
VENTILATION INSTALLATIONS
Galvanized sheets rectangular ducts – rectangular ducts sections and special
pieces
Galvanized sheets rectangular ducts– mounting images
VENTILATION INSTALLATIONS
Air grids
• This category includes : discharge openings,
intakes, air intakes, exhaust air grids.
• Discharge openings are posed in openings
executed in walls, or ahead of supply air ducts.
VENTILATION INSTALLATIONS
Air grids
VENTILATION INSTALLATIONS
Swirl discharge openings with /without distribution
VENTILATION INSTALLATIONS
Ceiling diffuser with adjustable outtake direction installed at the head of the duct
VENTILATION INSTALLATIONS
Regulating devices
• Regulating devices are mounted inside the ducts , or in the
discharge openings.
• - wings dumpers , mounted inside ducts , made from a rigid
plate sheet which rotates around a central fixed axis;
• -branch dumpers , mounted inside branch pieces, made from
a rigid plate sheet which rotates around an axis fixed at one
border;
• -shut off dumpers , mounted inside ducts or at discharge
openings;
• -adjustable blinds .

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