2 radiators not working

piperm87

Been arsing around with my rads for ages because of one thing or another. Im almost there now with getting the balancing sorted but the radiator on the landing and the one in bathroom are getting luke warm and thats it.. ive checked the pipes and the flow pipes going into the radiators are red hot but the returns are cold / same temp as radiators. The valves are open almost fully but it doesnt make a difference.

Would i have a blockage in the pipework thats effecting the return flow? Ive had the rads off recently to flush them through and there was abit of gunk around the lockshields but am at a loss as to why theres a lack of return flow. . All the other rads are working fine now. 

housebuyer143

Have you tried turning all the others off at the thermostatic valves apart from the ones that are not working? Potentially there is an airlock. Then turn them all back on if they start working and they should be fine then if that was the problem.

I had a similar problem and that seems to solve it. 

piperm87

Ive turned off a few of the bigger rads and it hasnt made a difference to those two.  Might have to try them all tomorrow to see what happens 

Mr.Generous

Sounds like sludge blockages to me, run a system cleaner for at least a week, pump on high, and shut off other rads until you get a flow through the blocked ones. You might have to do this a couple of times with a drain down, still much cheaper than a powerflush.

ThisIsWeird

Any chance of fitting a magnetic filter to the boiler return pipe, Piper? Then any sludge loosened by the additive will be collected and can be removed.

diystarter7

Hi OP

did you fully turn off the TVR's at any statge. Even fairly new TVR's, the pins can get stuck.

We had the above years ago on a fairly new CH ststem - me and my OH took of the massive double, roll top rad and emepited it it was clean and no difference - then when it was back on and on a cold summers night, i took the top of the tvr (not recommended) and managed to pull the pin right out - managed within seconds to stick it back in with getting scalded and the rad heated up like never before possibly a faulty TVR from new. Check the pins when cold but dont do it like i did ie when ch is hot or pully the pin right out. Check if the tvtr top is operating as it should be

Thnaks

plumb1_2

With the heating off, turn both valves of the radiator off, remove the air vent. Get a jug and bucket, put the jug underneath the open air vent then open the offending valve slowly. You should get a stream of water, pull enough through to allow for any trapped air. If nowt comes through gently tap the valve.

housebuyer143

piperm87 said:

Ive turned off a few of the bigger rads and it hasnt made a difference to those two.  Might have to try them all tomorrow to see what happens 

You need to literally turn them all off apart from one that isn't working and wait about 10 mins, then if that comes on, turn that one off and turn on the other that isn't working. 

Try that first. I was sceptical but everytime the system is drained down I have two rads which do not get hot at all. I follow this process and they always come back on very hot afterwards.

ChasingtheWelshdream

housebuyer143 said

You need to literally turn them all off apart from one that isn't working and wait about 10 mins, then if that comes on, turn that one off and turn on the other that isn't working. 

Try that first. I was sceptical but everytime the system is drained down I have two rads which do not get hot at all. I follow this process and they always come back on very hot afterwards.

I am far from a plumber, but just seconding this. Each time I drain down, the same two radiators stay cold, so I do exactly this and they always work again! In fact, I had to do that very thing this morning 🙂. Plumb_1 is my fall-back method but I have only needed to do that once.

piperm87

Thanks all i really appreciate it. Ive just tried it and turned off every rad apart from the one on the landing and there was no change. I did the same with the bathroom one and the same result. I know its  pex pipe under floor so im wondering if its kinked maybe when ive been moving rads around. Its only happened this winter though and has been fine over previous years which is weird

housebuyer143

piperm87 said:

Thanks all i really appreciate it. Ive just tried it and turned off every rad apart from the one on the landing and there was no change. I did the same with the bathroom one and the same result. I know its  pex pipe under floor so im wondering if its kinked maybe when ive been moving rads around. Its only happened this winter though and has been fine over previous years which is weird

Ah that's a shame, would have been great if that was the fix. Hopefully you get it sorted.