11
INSTALLATION - WATER PRESSURE
The product MUST be fitted with a Pressure Relief Valve. The factory fitted
Temperature/ Pressure Relief Valve can fulfil this function.
Expansion can take place within the cold water supply provided that both :
a) Backflow in the main is not prevented by any stop valve with check valve, pres-
sure reducing valve or similar
b) Hot water expansion does not enter a branch to a cold water outlet (see
Diagram to the right for expansion pipe lengths).
Additionally expansion within the cold water supply will not be possible if the
static supply pressure exceeds 0.41 MPa (4.1bar).
If any of the conditions in above cannot be met, expansion must be accommodat-
ed using an Expansion Vessel. To ensure all expansion takes place in the vessel a
Check Valve must also be fitted together with a Pressure (expansion)
Relief Valve (see diagram to the right).
If the static supply pressure exceeds 0.41 MPa (4.1 bar) a Pressure Reducing
Valve must be fitted to the cold main supply. If a Pressure Reducing Valve is
used, an Expansion Vessel must also be used (see diagram to the right).
