worcester combi 24cdi CH overpressure

[adove]

Too much pressure, creeps up to 3bar. I then release it down to 1.5bar, creeps up again.

Changed rad recently, accidentally over pressured refill (2bar) then released it back (1bar).

Refill key not in, so not accidental filling I assume.

Works fine however, but pressure causes release valve to let go.

Is it ...

Air pressure to low, or none existent in tank?
Leak through in heat exchanger?
Something else?

thanks for any advice ..

Al.

 

[COG]

If you never have to top up the water then it must be your plate heat exchanger ,its the only part that if faulty will pass mains water into your system water.

 

[cmyers_uk]

The symptoms you describe, on my Worcester 350 were caused by the diaphram in the expansion take breaking. To test there is a car tyre valve on the tank if water comes out when you press the valve the diaphram has broken.

Regards

Chris

 

[COG]

if your expansion tank had gone you would have to re pressure the system after it lost from the prv,if you never have to put water back in then it cant be your expansion vess.