VN0930027
Solahart Owner’s Manual – Thermosiphon Systems - Revision 3
21
EXPANSION CONTROL VALVE
(REQUIRED IF SATURATION INDEX E0.4)
COLD SUPPLY CONNECTION
The cold-water supply line to the water heater must be connected to the Male R¾ brass fitting on the cold pipe as shown in
the image above. The hexagonal flats of the cold-water inlet fitting must be held by a spanner to prevent the rotation of this
fitting when the mating fitting of the cold line is attached to it.
An isolation valve (stop-cock) and non-return valve must be installed on the cold-water line to the water heater. An
acceptable arrangement is shown in the diagram.
An Expansion Control Valve must be installed if the saturation index of the water supply e0.4. Refer to Saturation
Index on Page 6 for further details including Warranty limitations associated with it. The parts shown in the above image are
not supplied in the kit.
TEMPERATURE PRESSURE RELIEF VALVE (UNVENTED SYSTEM)
A TPR valve (Part No. VN0262002K) must be fitted to the tank to limit the tank water pressure to 1,000 kPa and the tank
water temperature to 99°C. It is MANDATORY that this TPR valve be fitted in all cases, except where the storage tank is
vented to atmosphere through a vent pipe.
The TPR valve must be fitted before the water heater is operated. Before fitting the TPR valve, make sure the probe has not
been bent. Seal the thread with a thread sealant such as Teflon tape. Make sure the thread sealant tape does not hang over the
end of the thread, ensuring it is at least 3 mm back from the end of the thread to prevent tape fouling the valve seat. Screw the
valve into the Pressure Relief Port of the tank. When tightening. When tightening the valve, use the spanner flats provided.
Do not use a wrench on the TPR valve body
Continuous leakage of water from the TPR valve or its drain line may indicate a problem with the water heater.
Warning:
Never block the outlet of the TPR valve or its drain line for any reason.
RELIEF VALVE DRAIN LINE
A DN15 copper drain line must be fitted to the temperature pressure relief valve. Connect the drain lines to the valves using
disconnection unions.
The drain line from the valve to the point of discharge must:
- be as short as possible;
- have a continuous fall all the way from the water heater;
- have no tap, valves or other restrictions; and
- be no longer than 9 m with no more than three bends greater than 45°
Cold Water Line Inlet
Cold Pipe
R3/4 Fitting
