i've had the same probelm in my old housemate.....

theres an external thermostatic valve which has a temp probe conected either into the main cylinder, or on an outlet pipe from the cylinder..... these valves can go after some time, such as my old one! if it IS the valve it needs replacing, think they're about ?75-?100, can replace it yourself if you know how to drain down the cylinder and isolate (otherwise worth paying about ?150-?200 for a plumber, inc. new valve).

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Posted By: Cheltenham_Canary, Nov 11, 15:01:04