Base of radiator stays cool

Innys

Hi all

I have a problem with my double radiator in the downstairs hall and wonder if anyone can help me. It's a brand new Stelrad model and was fitted fairly recently.

When I have the heating on , though, the top of the radiator heats up quickly, but the base stays only lukewarm, at most.

Any ideas what the problem may be? I will be calling the plumber who fitted it back, but before then, I was wondering if anyone could help.

Thanks

I

keystone

I'm just going to wait for the "you need a powerflush bcause the radiator is full of sludge" brigade to arrive.

Cheers

















PS OK then - can't wait too long . Was the system rebalanced when the new rad was installed. It sounds like a circulation problem to me.

Innys

All the radiators in the house were replaced at the same time with TRVs and lockshield valves on each. The plumber said he had rebalanced the system, so I can't understand why I'm still having problems....

macman

Cold at the base does indicate sludge, that doesn't mean that a powerflush is required though-remove the rad and flush manually.

Alias_Omega

As MacMan says..


If both the inlet and outlet pipes get hot, and the bottom/centre of the radiator is cold then there must be something inside it to stop the heat transfer.

Removing the radiator can be a simple job, close both radiator values though be sure to count how many turns each one takes so you can put them back the same. Once the valves are closed, you just need to undo the valves from the radiator catching the water with a tower etc. Its a 2-person job ideally, have one person remove the radiator and one person to manipulate the valves out of the way, keeping the radiator level.

Once its away from the wall, tip it towards a bucket/bowl to catch what comes out of it. It wont be nice, maybe black/brown colour. You can now take the radiator outside and flush it out with a hose pipe etc.

Fitting is just the same, one person to put it on and one to move the valves. Once its back on the wall, filling the radiator is not as simple as opening both valves. You will need to bleed the radiator out of all the air and restore the system pressure afterwards.

Alias

Idonex

Innys wrote: »

All the radiators in the house were replaced at the same time with TRVs and lockshield valves on each. The plumber said he had rebalanced the system, so I can't understand why I'm still having problems....

Would love to know how you get this fixed. I have two radiators in my house that are doing the same. Stone cold at the bottom, warm at the top. No new radiators, in fact everything was working fine this time last year. Started happening when we started using the heating again a month or so ago.

If i feel brave i might take them off and stick a hose through them!

MWOOLY10

You may just have an air lock in the system.

Go round the house and turn off all the TRV's on the radiators and leave the one thats cold at the bottom and put the heating on, it should force the air out and thus making the radiator hot. when its hot go round and open all the other TRV's.

If you get another cold at the bottom, repeat the sequence one radiator at a time, until all radiators are hot..

May not be the problem but worth trying, could save you alot of money on a power flush

DVardysShadow

macman wrote: »

Cold at the base does indicate sludge, that doesn't mean that a powerflush is required though-remove the rad and flush manually.

And how does this sludge arise in the base of a new radiator? Don't tell me it was pumped in, because I don't believe that the volume of sludge required could reside in the pipe and get transported into the radiator. Keystone is right on this one. It is a circulation problem, either due to balance or an airlock.

Alias_Omega

Our boiler is upstairs, the upstairs radiators are supplied from the floor, the downstairs radiators pipes are surface mounted from the ceiling.

I would expect that any sludge would fall into the downstairs radiators as when the system is off, gravity will have an effect and any sludge in the vertical pipes will fall into a mass, then pumped into the radiator once the system is back on.