only one radiator working?

wallofbeans

We've just turned the heating back on and only one of our radiators is working (spare room - the rad that is newest and replaced less than 6 months ago) all others are stone cold.

I've tried bleeding them all but no air at all.

I am hearing a clunking of the pipes from time to time, like is stuck somewhere but i cant tell where.

Any ideas on what I could try next before i call a plumber?

Thanks.

david39

I'm not a central heating expert but have you checked the water pressure level in your system? It may well have dissipated over the summer. The radiator that's working may be doing so by convection and not by the water flowing from the pump.

There's usually a guage on the boiler somewhere (you'll probably need to remove an inspection panel or the casing to reveal it).

Usually, this should be showing as 1.5-2.0. If it's much lower than this, then there is not enough pressure in the system for the pump to drive the water round it. My system stops warking when it's just above 1.0.
You will need to add water into the system to increase the pressure - there will be a tap somewhere on the mains-water-feed pipe into the boiler - it will be inside the casing or inspection cover.

Slowly open it and allow the pressure to rise to about 1.5 - do not let it go over the red line that shows maximum pressure! My boiler has two taps in-line - I have to open both to allow the water to flow in.

I have a friend who is a boiler engineer and he says he makes most of his money from call-outs to people who only need their pressure increasing as above.

If you are not confident in what you are doing, though, call an engineer.

wallofbeans

Thanks for the advice. You could be right.

Its an Optia HE15 boiler. Any ideas how to remove the casing? Cant figure it out!

Browntoa

is it not behind the grey part at the bottom of the bolier ??

wallofbeans

Browntoa wrote: »

is it not behind the grey part at the bottom of the bolier ??

there's a flap at the bottom section but behind that there's only an on/off switch and a 1-6 marked twisting knob. no temp gauge.

Norman_Castle

If the only radiator that is working is the one that was replaced six months ago is it possible the installer switched off the other radiators and forgot to switch them back on.Was the heating tested after fitting the new radiator and have you tried asking whoever fitted the radiator.I am no expert but I think if the pressure is too low or high the boiler will switch off and therefore not heat any of the radiators.

macman

Is this a combi boiler or conventional system?

wallofbeans

im not sure about most of them but i know the bathroom one was working quite recently (and since the spare room radiator was changed) but its not working now. Something has changed between the new rad being fitted and now.

wallofbeans

macman wrote: »

Is this a combi boiler or conventional system?

dont think its a combi, old house and we still have hot water tank in cupboard in bathroom. Two water tanks in loft.

Hot water working fine by the way.

macman

Fine, so if it's a conventional boiler then no issue with repressuring the system or looking for a pressure gauge.
Get up in the loft and check the header tank,it may be that the ballcock has jammed over the summer. Check that there is water in the header tank and that it flows in OK when you press the ballcock down. Apply some WD40 if necessary so that it moves freely.
Also check the operation of the motor valve (probably near to the tank in the airing cupboard), try moving it manually in case it's also stuck.

wallofbeans

macman wrote: »

Fine, so if it's a conventional boiler then no issue with repressuring the system or looking for a pressure gauge.
Get up in the loft and check the header tank,it may be that the ballcock has jammed over the summer. Check that there is water in the header tank and that it flows in OK when you press the ballcock down. Apply some WD40 if necessary so that it moves freely.
Also check the operation of the motor valve (probably near to the tank in the airing cupboard), try moving it manually in case it's also stuck.

wouldnt the hot water be affected by the header tank not working?

and the motor valve seems fine. the lever moves up and down without problem. should i check it for anything else?

to the loft!