I am having issue whereby replacement wall thermostats are repeatedly failing - all with the same issue - in that the relay to switch the heating off when the thermostat reaches the correct temperature works fine to start with then fails to work. Once that happens, it never works again. I've replaced the unit twice in the last two months. It will work for a random period of time, and then fail.
The three way valve seems to work fine when forcing hot water and/or heating or both, so I don't think that's the issue.
The Boiler is around five years old and seems to work fine too. All is good for a few weeks/sometimes months after replacement of the stat, then the unit eventually fails. I've tried Honeywell, Drayton, Solus - all seem to fail with the same relay issue. There's very little on the internet it seems on this issue, so wondered if anyone had any ideas for a solution. Job for a central heating engineer or electrician, the usual dilemma??
The three way valve seems to work fine when forcing hot water and/or heating or both, so I don't think that's the issue.
The Boiler is around five years old and seems to work fine too. All is good for a few weeks/sometimes months after replacement of the stat, then the unit eventually fails. I've tried Honeywell, Drayton, Solus - all seem to fail with the same relay issue. There's very little on the internet it seems on this issue, so wondered if anyone had any ideas for a solution. Job for a central heating engineer or electrician, the usual dilemma??