Combi Boiler
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roddymcdowall
Apprentice
Apprentice
Posts: 7
Joined: Mon Nov 09, 2009 3:10 pm

Combi Boiler

by roddymcdowall » Mon Nov 09, 2009 3:23 pm

My boiler which is an Ideal - Mexico type recently stopped turning on. I checked the power supply to two solenoids which controlled the opening of a valve for the heating and the hot water as well as the live supply to the boiler and the power appeared to be reaching both solenoids.

With the power turned off I did some resistance checks and it appears that the heating thremostats leads which are black, red and green(used as a reurn to neutral) are grounded. I could not figure out why there was a lead for neutral on the thermstat (perhaps someone would explain).


Since the hot water tank has electrical elements supplying it as well the thermostat for hot water was open so I shunted the thermostat and the boiler kicked on.

I also disconnected the heating thermostat and put live power onto the solenoid but it still did not enegise.

So as a short-term solution I have wired the power straight to the boiler which can be switched off via the power supply or the boiler switch.

I think I have a bad solenoid which might have been damaged by the thermostat being shorted to earth. Any comments?

Anyway if that is so in the short-term I could switch the solenoid from the hot water to the heater for the moment. How easy is that to do? Is the valve that the solenoid is open an integral part of the solenoid or is independent of it and attached to the water pipe separately?
Is it just a matter of me switching over the solenoids without having to worry about seals on the water pipes? Any advice would be apprecaited?