Potterton puma 80 - low pressure

[andybib]

Need help!! - heating goes on and the pressure goes to 3bar and sometimes blows out of relief valve, when its turned off it drips from relief valve until all pressure is lost and low pressure light comes on.

Have replaced relief valve and its still happening! - any ideas?

Andy

 

[Bahco]

Is your filling loop still connected to the boiler

 

[andybib]

i'm sure it is, I have to manually fill the boiler by a filling loop when I loose all the pressure.....

 

[Bahco]

Disconnect it from the boiler end only, and see if it is letting by water even tho it is turned off.
If it is you have found your problem.
If not it could be your evpansion vessel needs attention

 

[andybib]

ok but its only happening when the heating is on, if the boiler is on standby the pressure stays the same....?

 

[IanDB]

The expansion vessel needs recharging/replacing. If this is not at the correct pressure then the water pressure rises - as BAHCO says.

 

[andybib]

Thanks for info. Is recharging the expansion vessel something I can do myself?

 

[IanDB]

It's buried in here http://www.diynot.com/forums/viewtopic.php?t=19131 also here http://www.diynot.com/forums/viewtopic.php?t=18468&postdays=0&postorder=asc&start=0

 

[andybib]

To all who replied, thanks a million for the advise you all gave. It was the EV, got a bike pump to it and put in 1 bar and it seems ok at the moment, even if it slowly looses pressure I know I need to change the EV to rectify.

Thanks again!

Andy