The Expansion Vessel is suitable for systems with a static head of up to 5 metres (16.5ft) i.e. the vertical
distance between Expansion Vessel and highest point of system, usually the top of bedroom radiators. If the
static head is greater than 5 metres, then the charge in the vessel must be increased to equal this higher
static pressure. The pressure can be increased if required by simply pumping up the vessel with a standard
air type pump and checking the pressure with a tyre gauge with the system at zero pressure. A Schrader type
valve is provided on the vessel for this purpose (
see note below
).
NOTE:
The air charge should not exceed a pressure of 1.5 Bar (22 p.s.i.).
1) Expansion Vessel Requirements
Page 14
2) Storage Tank
An insulated tank providing storage for heated water that is used via the Plate Heat Exchanger for domestic
hot water production.
3) Pressure Gauge
The Gauge (0-6 Bar) (mounted on the Control Panel) is provided as a visual indication on the water pressure
within the system.
A pressure below the set Cold Fill Pressure indicates the system requires "topping up".
4) Pressure Relief Valve (3 bar)
Supplied fitted on the Storage Tank.
5) Manual Air Vent
A Manual Air Vent is supplied on the Boiler Primary Heat Exchanger and the storage tank. Routine venting of
radiators is still advised.
6) Circulating Pump
The pump is fitted to the Flow Pipe as a circulating pump for the Heating System and the Domestic Hot Water
Heat exchanger.
7) Tundish (not supplied)
Provides a visual indication of water flowing from the Pressure Relief Valve.
Vessel Charge and Initial System
Pressure
bar
0.5
1.0
1.5
psi
7.3
14.5
21.8
Expansion Vessel size
Total water content of system including 40 litre tank using expansion
vessel supplied
12 litres
litres
150
110
75
gallons
33
24
16.5
For systems having a larger capacity multiply
the total system capacity by the factor to obtain
the total minimum expansion vessel capacity
0.08
0.11
0.16
Page 21 of 57
Installation & maintenance manual for Camray 5 Combi External Boilers
14/04/2005
file://D:\PL61500\PL61500.htm
