radiator balancing

[apcdave]

Hi chaps,

It's the usual scenario.... 9 out of 10 rads all heating fine / the one which is not reaching the same temp as the others is in an upstairs bedroom. I have just spent most of today trying to get it to heat up but without much success. Some of the other upstairs rads have TRV's fitted on the return side - would this make any difference when trying to balance the system? or does it not matter and you just close or open the flow valve as you would a lockshield?

cheers

dave

 

[GQuigley67]

is it heating up at all or is it just luke warm ?

 

[apcdave]

it's actually quite warm but not as hot as others

 

[maul]

most new trv are bi directional they work either on flow or return.
have you tried shutting all the other rads down to see if its a partial air lock ?
forcing all the flow through just that one rad should clear it if its an airlock or a bit of sludge restricting the flow

 

[apcdave]

Hi Maul - yep - have closed all other rads down and sure this one heats up great. Thing is as soon as I open up the others it's temp drops. So definitely a balancing problem

 

[GQuigley67]

what setting is the pump on ?

 

[apcdave]

the pump is on the highest setting

 

[Bartdude]

It sounds like you need to balance the system, the radiators that are hottest can be turned down,this will push the heat to the problem radiator. Take off the cap on the lockshield valve and turn the spindle clockwise to close it,try a couple of turns to start with.You have to keep checking the radiators until they all "balance" out!

 

[jambo]

Full system powerfush would not go a miss should have a differance of 20 degrees between flow & return when balancing

 

[doitmyself]

... should have a difference of 20 degrees between flow & return when balancing

Not necessarily true. Some boiler work with an 11 degree difference. If you have a 20 degree difference across your radiators their output will be reduced by about 15%.