Radiator balancing

[Nigel Watts]

My hot water and radiator system is very out of balance. Until the boiler was serviced recently the hot water was too cold in the mornings yet the radiators worked reasonably well. The plumber has solved the hot water problem by overhauling the valves and increasing the hot water flow (probably by opening up the valve where the coil comes out of the cylinder) but the radiator system now isn't working properly. The first floor, where the tanks and pump are, is fine as is the secod floor, but the ground floor radiators are not warming up properly yet the underfloor heating in the basement seems to be working OK.

I have seen a clip on You Tube which suggests you should use a meter to measure the temperature difference between the inlet and outlet pipe on each radiator and adjust the valve until it is around 12C, but when I asked at a plumbers merchant where I could get such a meter he looked blank. I have made a start by closing up valves on radiators which get hot and opening them up on those that don't, but the basis on which I have been doing so has not been very scientific.

Is it necessary to use a meter and how does the underfloor heating system come into the picture? Any advice gratefully received.

 

[Nigel Watts]

.

 

[Keith Bowman]

Not sure about meters as such, or even about whether you have been give useful or useless advice (!), but you can get infra red thermometers which you simply point at the thing you want to measure. Some cost a lot, some don't. For your purposes, one of the cheap ones ought to suffice, eg http://www.maplin.co.uk/pocket-infrared-thermometer-220790
Do, please, let us know how you get on.

 

[Flyfisher]

oooh - I like the look of that! ( I have a soft spot for gadgets :lol: )

Mind you, I'm not entirely sure of the usefulness of displaying 1/10th of a degree when the accuracy is +/- 2 degrees - by hey, it's only £20.

 

[Owain]

The method is described in the news:uk.d-i-y wiki

 

[88v8]

The method is described in the news:uk.d-i-y wiki

Yes.
After each change, one may need to leave it half an hour to heat-soak at the new setting. You may find that you end up with some of the lockshield valves very nearly closed, that's OK.

The system balance should not be affected by the hot water - if there is not enough flow to run the water and the heating simultaneously, then the pipes are too small, or the pump is too small or not running at a sufficient speed.

Did it mention to turn up the room stat so the system won't cut out, and the boiler to max so it will keep firing? ? Well, if you don't it will take a looooong time. Choose a cold day or just wear shorts & T, the house will get hot. Once, I did this in the summer - some inappropriately stored wine blew its corks out.

Ivor

 

[Keithj]

I spent ages trying to balance ours, and got it nearly right just before we had the repair work done. As part of that, our friendly local plumber fitted thermostatic valves on each radiator and balanced the "return valve" on each radiator to even up the flow. It works fine: we can set each room to the temperature we want: the only effect of turning one room up is that the other rooms take a bit longer to warm up.

It wasn't that expensive in the grand scheme of things, and I'd do it again like a shot.