what have they done to my CH?

[Marina]

Hello,
Potterton Puma80 combi - small flat, only 4 rads, working perfectly both CH & HW until a couple of days ago when builders came in. Part of their work was to reposition one of the rads from one wall to the opposite one. They did that and since then the CH hasnt' worked properly - the nearest rad to the boiler heats up, the next 2 are lukewarm, the last one (the repositioned one) stone cold! And the boiler's making "clunking" noises.... the rads have all been bled a number of times (but not the pump). Is there anything I can do myself to rectify this mess and get a bit of heat (until Monday when they will be back and I'll give them hell???)
Thanks
marina

 

[Rob]

does the hot water work ok?
coulde be that sludge has deposited in the diverter valve/wax capsule, as a result of draining down.

from experience these boilers do require the pump to be vented after drain down. was it not all tested when they re-filled it?

 

[Marina]

thanks for your reply - the hot water works fine.
we had problems in the past with the diverter valve which we then got replaced, but at the time no heating at all was coming thru the rads. This time is different in that *some* heating is filtering thru. One of the builders said it's probably a problem with one or more of the rad valves (got stuck in "close" position) but he's no plumber.
As far as I know no check was done after re-fitting.... GROAN!

 

[ChrisR]

Very top left of the boiler is an air vent, whose black plastic cap must be left open for it to let air out. Probably will leak if you do, so let air out then do it up again. They also block up and need replacing - cheap though.

 

[Marina]

just tried that - left it open for a while, no water coming thru at all - didn't work. I guess I'll just have to wait till Monday.
Thanks anyway
Marina