INSPECTION NON-RETURN VALVE

Set Appliance State:

Isolate Mains Power to appliance as per TOPs P4

Ensure boiler is cool
Drain primary system water from boiler
Remove casing cover for internal by-pass (see note)

Observation:

Inspect the non-return valve for restrictions and/or blockages.
Check the operation of non-return valve, gently push the center of the valve, its operation should be smooth and easy to push (see note).

vk compact 25a din case off display down.gif

Casing cover

Non-return valve

Note.
Take appropriate precautions regarding primary system water which may still be present in the boiler when the valve is checked or removed.