worcester bosch 240 problem

[specialized]

can anyone help before i call an expensive man in. i have a worcester bosch 240 combi boiler.
since switching the heating on for winter it has permanently leaked cold water through some sort of over flow pipe on the outside wall!

any ideas?? thankyou

 

[kevplumb]

prv is leaking needs cleaning / changing

also check boiler pressure

fill loop is closed

expansion vessel pre charge

then have a cuppa

 

[gblades]

Thats the PRV (pressure relief valve). Either it is faulty or you have too much pressure in the system.
What pressure is indicated on the gauge on the front of the boiler?

It should be around 1.2 when cold and up to around 2.0 when hot. If it rises too far you might have air in the system or a faulty expansion vessel.

If it too high when cold you might have a leak in the heat exchanger or filling loop letting mains water into the system.

 

[specialized]

thankyou all

whats the easiest way to lower the pressure? I'm too high after topping up after bleeding..

 

[gblades]

A bit of garden hose attached to the drain plug (near the radiator valve) of a radiator.

If its only a bit too high you can just vent a bit of water out of the vent plug into an old cloth.

 

[specialized]

Fantastic

thankyou all for help and advice i'll have a bash