C/Heating Pressure Guage-Low Reading

[tonyd]

I have a Worcester 9.24 Electronic Combi and have recently changed the filling valve on the filling loop due to it leaking water into the system.

My pressure reading has always been about 1bar but noticed that it had began to rise. At the point when it went over 3bar (safety valve rateing)my first action was to check all rads for air (non found) than manualy operate the safety valve. When the pressure continued to build-up I then turned of the the supply and found that it was the fill valve.

Having fitted the valve and set the pressure back too 1bar, I now find that the system is loosing pressure and the gauge now reads 0-0.1 bar and rises to 0.3bar when the heating is on.

I have checked the safety valve outlet pipe and water is leaking from the valve.

All the rads appear to be operating properly and there are no unusual sounds from the system

Any suggestions?????

 

[ChrisR]

"I have checked the safety valve outlet pipe and water is leaking from the valve. "

There's your answer. Try to reseat the valve by turning the head (it will make a clunking noise). Often you have to get the valve replaced once it has leaked.

Remove the filling loop when not in use.

 

[oilman]

Often you have to get the valve replaced once it has leaked.

Remove the filling loop when not in use.

This is where the gas boys and I differ, I have never had a permanently leaking PRV on an oil combi after opening for testing. If it did leak, opening it again and blasting some water past it has cured the leak, so if you have to have a combi, make sure it's oil.

All sealed system owners please note.

As ChrisR says, remove the filling loop when not in use. There is a regulation reason so that backflow from your heating system will not contaminate your drinking water supply. There is a safety reason, if your PRV sticks (and it has happened) and the filling valve leaks, you can burst the expansion vessel. (That's happened too).

 

[tonyd]

Thanks guys, I opened the valve a few times as you suggested and touch wood it appears to have solved the problem, however I've got a new valve (just in case).

Cheers