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INSTALLATION
INSTALLATION
Boiler Size
The minimum total boiler power required is the
sum of the power required for space heating
which should be calculated in accordance with
BS 5449 and the power required for producing
hot water which can be read from the table to
the left.
Expansion Vessel For Sealed Heating System
The table opposite can be used for sizing the
heating system expansion vessel. The water
content of the Torrent primary heat exchanger
is listed in specification tables on pages 6
and 7 and a figure of 4.5 l/kW of installed
radiator capacity can be used for a preliminary
assessment of the water content of the heating
system.
The expansion vessel requirements shown in
the table are based on a maximum boiler fl ow
temperature of 93°C. The expansion vessel
must be suitable to accommodate the change
in volume of water in the heating system when
heated from 10°C to 110°C as specifi ed in BS
5449:1990 clause 16.2.
Feed And Expansion Tank For Open Vented
Heating System
The potential expansion of all the thermal stores
in the range is shown in the table opposite,
alongside the capacity for expansion, in our
standard F & E tank, which can be supplied as
an optional extra.
Expansion for all other open vented systems
connected to the store must be added to this
fi gure. So, as a preliminary assessment of the
water content of the attached open vented
systems, a fi gure of 4.5 l/kW of radiator output
can be used. For example, 20 kW radiator output
would have a system volume of 90 litres, and
potential expansion of this would be 3.6 litres,
and 10 kW would be 45 litres total volume and
1.8 litres for expansion.
Allowance for domestic hot water for sizing the boiler
Torrent model
Allowance for domestic
hot water heating (kW)
Full divert mode
Flow share mode
140
0
2
170
0
3
210
0
3.5
280
0
4.5
350
0
6.0
450
0
8.0
Expansion Vessel Requirements
Safety valve setting
3.0
Vessel charge
pressure (bar)
0.5
1.0
1.5
Initial system charge
pressure (bar)
0.5
1.0
1.5
2.0
1.0
1.5
2.0
1.5
2.0
Total System
Volume (litres)
Expansion Vessel Volume (litres)
25
2.1
3.5
6.5
13.7
2.7
4.7
10.3
3.9
8.3
50
4.2
7.0
12.9
27.5
5.4
9.5
20.6
7.8
16.5
75
6.3
10.5
19.4
41.3
8.2
14.2
30.9
11.7
24.8
100
8.4
14.0
25.9
55.1
10.9
19.0
41.2
15.6
33.1
125
10.4
17.5
32.4
68.3
13.6
23.7
51.5
19.5
41.3
150
12.5
21.0
38.8
82.6
16.3
28.5
61.8
23.4
49.6
Thermal Store
Potential
Expansion of
Water in Store
(litres)
Minimum Number of Feed and
Expansion Tanks
(16 litre model inc. 10 litre expansion)
TGH140
OV model - 6.6
SP model - 6.6
1
TGH170
OV model - 7.0
SP model - 7.0
1
TGH210
OV model - 9.6
SP model - 9.5
SOL model - 8.0
1
TGH250
OV model - 10.6
SP model - 10.1
SOL model - 11.1
2
TGH350
OV model - 16.5
SP model - 16.3
SOL model - 16.4
2
TGH450
SOL model - 21
3
Expansion of all connected open vented systems must be added to the store
expansion when choosing the size of the feed and expansion tank.
The weight of each tank when full is 27kg (not including pipework and valves).
Summary of Contents for Torrent GreenHeat HP TGH170-HP
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