Radiators Not Warming Up

moneybunny123

There are certain radiators in my house that just aren't warming up. Occasionally they do, but generally they don't even feel aired.

Yes, I've bled them, but water comes out straight away - no air at all.

What could be the issue?

tonyh66

could be that the radiators are not balanced and all the rads nearest to the pump are taking all the heat out of the system. turn off the hot radiators and see if the cold ones get hot.

macman

Where are the 'certain rads' in the house? At the top of the circuit maybe?

ariba10

With the system on, try turning off the rads that are working.

If the cold ones then warm up it is more than likely the system needs balancing.

Not a difficult job, but time consuming.

moneybunny123

The radiators that don't get warm are on the middle floor of a 3 storey house (although the rads on the top floor are controlled by a separate thermostat). 5 radiators on the middle floor all get red hot, but 3 of them - 1 in particular - rarely get warm. The airing cupboard (with tank and pump) are on the top floor, the boiler is on the ground floor.

How do you balance the system? What does that involve?

ariba10

I cannot post a link from where I am at the moment but if you Google " Balancing Central Heating" you should get something to work with.

JohnB47

Your system sounds a bit complicated (thermostat control on the top floor). Just to confirm, was this working before? - When did it stop working?

gazman100

Doesn't sound like it (as multiple radiators) but have you checked the valves aren't stuck? Happened to me with a single cold radiator and very issue to fix/rule out (in fact is was the spring in the detachable valve head thing that had failed). Just google "radiator valve stuck".

moneybunny123

gazman100 wrote: »

Doesn't sound like it (as multiple radiators) but have you checked the valves aren't stuck? Happened to me with a single cold radiator and very issue to fix/rule out (in fact is was the spring in the detachable valve head thing that had failed). Just google "radiator valve stuck".

No, the valves all move freely. And, as I said, the radiators DO occasionally get hot - but not very often.

moneybunny123

JohnB47 wrote: »

Your system sounds a bit complicated (thermostat control on the top floor). Just to confirm, was this working before? - When did it stop working?

There are two thermostats (one on the ground floor which turns the heating on on the ground and middle floor) and another thermostat on the middle floor which controls the heat on the top floor.

The thermostats all work. Everything works except for these 3 radiators that 80% of the time just don't get very warm at all, despite being full of water.

Ruski

Have they got TRV's on them and did you turn them off recently??

Russ