DIY Doctor UK DIY Forums

Hi, I have a 2 zone system supplied by an oil fuelled boiler. The downstairs zone will only work if the upstairs or hot water systems are running. If I turn on the downstairs separately the boiler and pump come on for about 3 secs then shut down. If the water or upstairs are on the hot water is pumped through the whole system. Each zone has it's own motorised valve and these seem to be working. Help.

As far as the two zones are concerned, the boiler, pump etc are working - so it has to be the motorised valve or room thermostat on the problem zone at fault.

Assuming it has worked at some point rules out a wiring problem.


htg

Thanks, the room stat seems OK as it switches the boiler on and off when the hot water is also on. I had ruled out the motorised valve as again the radiators warm up when the hot water is on also. Can they jam in a semi open state?

Thanks again for your help.