Zero volts at the room stat

[whydowebother]

Hi everyone. I have been trying to fix a central heating problem with help from people on the plumbing forum. Someone suggested I check there is 240V to the room stat, which I have done, and I seem to have an electrical fault.

The room stat is a Honeywell T6360, and I have tested it with a multimeter by placing the red lead on Terminal 1 (brown), and the Black lead on Terminal 3 (black). There is also a grey cable to Terminal 2 and earth to Terminal 1. The test shows zero volts on my multimeter (which does work), so unless I'm using the meter wrong (which is not unlikely), I seem to have no power to the room stat.

The next snag is that I don't know which circuit the stat is connected to, and in any case all the RCDs are still on, so why would the power have failed in the first place? Could there be another fuse or switch somewhere I don't know about (the house was completely rewired 5 years ago, so there shouldn't be any dodgy wiring...)?

Very grateful if someone could help - electrics is not my strong point (as you may have gathered), but I'd like to be able to diagnose the fault, if there is one, before I have to call an electrician.

Thanks very much for your help

 

[holmslaw]

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[whydowebother]

I have tested the unit again and got 240V between Terminals 1 and 2 with the heating switched on, so it looks like the unit works after all. Thanks for your help