DIY Doctor UK DIY Forums

We have an Oil Central Heating System with honeywell control.Recently the water in the main hot water tank is heating up when only the heating control is on.I do not really understand this,could there be a problem with two way valve.We only use the system with either hot water or heating on but not both together.Any advice would be appreciated.

ian0109,
Assuming that in the past you could select CH only, then the motorised valve sticking partly open is the most likely cause.
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