Powermax 155

[dorcas5]

Hi,
The pressure slowly falls over 24 hours, I have pumped the PV to 1.5bar the valve appears to hold ok checked with soft soap and checked the prv outlet, (dry).

The system works ok rads heat up, hot water fine, what am I missing?
Thanks,
JC

 

[Agile]

A leak on a rad valve or pipework?

When the heating is started from cold how high does the pressure get as it warms up?

Tony

 

[Onetap]

Hi,
The pressure slowly falls over 24 hours, I have pumped the PV to 1.5bar the valve appears to hold ok checked with soft soap and checked the prv outlet, (dry).
JC

Expansion vessel diaphragm failed. If the air you've pumped in has been lost, it's fairly certain.

Water discharged from the PRV only when the system is hot? The expansion vessel is often undersized on the Range Powermax by those who neglect to take account of the 100 litres of watre in the boiler thermal store. The Potterton HE Powermax is different.

You should isolate and drain the expansion vessel so that there is no pressure on the water side, before topping up the gas charge.

Shut the valves on the heating F&R pipes and see whether the heating system holds pressure. If it does, then possibly a leak inside the boiler.

 

[dorcas5]

Thanks for the replies.
The pressure rises to 1.7.

If the diaphragm has failed will water exit from the charging valve if depressed?

I guess if it has failed a new vessel will be reqired

 

[superdupergasman]

There is nowt wrong with you vessle if the Saftey blow off is dry and the pressure only goes to 1.7bar when heating is on.

You are looking for either a leak on the CH pipework or the plate heat exchanger can pinhole and act like a venturi sucking the water out the heating system. The later is a very rare occurance hovever and usually the pressure rises.

So get going around on you hands and knees looking for leaks and tracing the pipework!

Have fun

 

[dorcas5]

Thanks gasman,