Replacement Of Parts - Potterton Combi 80 Installation & Service Instructions Manual

5. Replacement of Parts - Page 26
WARNING: Before attempting to remove any component from this appliance, first disconnect the mains electricity supply by
removing the plug from the wall socket or by switching off the appliance at the external isolating switch. Note: The appliance
stand-by switch must not be used as the means of isolating, as this switch does leave parts of the appliance electrically live.
IMPORTANT: After removal or replacement of any gas carrying components a test for gas soundness must be made.
Isolate the Gas
Isolate/Drain the Water
Central Heating:
Domestic Hot Water:
The supply should be isolated at the boiler gas service cock (one quarter turn of square
spindle).
When draining and removing water carrying components ensure that the control box is
suitably protected from accidental damage.
Reduce system pressure at an external drain tap then close the isolating valves at the boiler.
Remove the drain screw from under the pump manifold and drain the system into a suitable
recepticle.
Close the isolating valves at the boiler and open the hot water taps to reduce the water
pressure in the boiler. Remove the drain screw in the cold water isolating valve and drain into
a suitable recepticle.