(v)
There must be no permanent connection of mains water to the boiler
system.
(vi)
The installation must be designed to work with flow temperatures of up to
110
o
C. All components of the system including the heat exchanger of the
indirect cylinder must be suitable for a working pressure of 3 bar and a
temperature of 110
o
C. Care should be taken in making all connections
that the risk of leakage is minimised.
Table 3.7.2 Expansion Vessel Selection
0.156
0.109
0.0833
Multiplying factor for other system
volumes
46.8
32.7
25.0
300 litres
42.9
30.0
22.9
275 litres
39.0
27.2
20.8
250 litres
35.1
24.5
18.7
225 litres
31.2
21.8
16.7
200 litres
27.3
19.1
14.6
175 litres
23.4
16.3
12.5
150 litres
19.5
13.6
10.4
125 litres
15.6
10.9
8.3
100 litres
11.7
8.2
6.3
75 litres
7.8
5.4
4.2
50 litres
3.9
2.7
2.1
25 litres
Volume
Vessel
Expansion
Total Water Content of system
1.5 bar
1.0 bar
0.5 bar
Vessel charge & initial system
pressure.
3.0 bar
Safety Valve Setting
WD500
Chapter 3 - Boiler Location
The Keston Q37 & Q37P Boilers
Installation & Servicing Instructions
Page : 15
RETURN
Valve
Safety
Check Valve
Double
By-pass
Stop Tap
BS 1010:2
Test
Cock
Hose
HEATING CIRCUIT
FLOW
Vessel
Expansion
L/S
bib tap
Hose Union
Air Vent
Keston Q37
Figure 3.7.2 : Sealed Systems Diagram
Cock
Drain
Connector
after filling)
(disconnected
Hosepipe
