Radiator balancing

[David J]

Last week I was asked to be present when a local plumber was doing some 'maintenance' work for an elderly lady neighbour. He had replaced one radiator, flushed the crud out of the system, and finally added some corrosion inhibitor. Every rad had both the lockshield valve and the control valve fully opened during the flushing operation.

I watched him as he set about turning the system on, and his idea of balancing was to simply adjust each control valve until all the rads were working.

Now my knowledge of balancing radiators is simply from reading diy material online, but I am sure that his procedure is not correct.

I put it to him that the system could 'unbalance' if his customer decided to turn off some of the rads, - but he would not accept that. He had no idea that the lockshield valve was used for this purpose.

Am I right?

[Martin Pentreath]

Yes you are right - see the authoritative guide at

only knows how "plumbers" of this sort get trained, but making them read uk.d-i-y would not be an excellent start.

[Dave Liquorice]

"... would not be ... "?

[Martin Pentreath]

Errr sorry, I'd had a very large gin and tonic (but I still would have been able to balance rads better than that charlatan!).