It didn’t do this constantly when the central heating was on last year, only when heating came on. Now it is a constant clicking even when heating is off, and not just every few seconds or anything - it’s like a car ticking over. Also it is flashing orange and red lights in time with clicking.
Boiler itself is working fine, as is heating, and I have changed the batteries in the wireless thermostat (dial type) just in case. I think the thermostat is pretty old and it isn’t branded so is hard to google for troubleshooting (I have checked all over both thermostat and receiver).
Does anyone have any ideas? Should I just bite the bullet and get a new thermostat fitted?