Immersion Heater Thermostat

Immersion heaters now have to have two-stage thermostats - the normal stage which turns on and off to control the water temperature, and an emergency stage - set to a higher non-adjustable temperature - which cuts out, and stays off until manually reset - to stop the water from boiling in the event that the normal stat fails in the ON state.

It sounds as if one of these functions isn't working properly. If the water is (very) hot when it cuts out, the main stat has failed and the emergency one has saved you from disaster. If it cuts out when the water is only slightly warm, there is something wrong with the emergency stat. You'll need to replace the whole thing, anyway.

Are you in a hard water area? Some immersion heaters are suitable for hard water and some are not. If you have the wrong type, it's possible that it (the immersion heater)could be over-heating due to limescale - without actually heating the water properly.

Thanks Set Square

I have been and purchased a new thermostat even though the previous on had only been in position for about a week. I am just waiting to se whether this will keep tripping and needing re-set. I am definately in a hard water area. How do I know what is the correc immersion heater as I have just bought one from Homebase and it talk about hard water tempretures. The previous heater I changed was covere in limescale and only lasted a few months

Cheers

Chri

-- chrisdeehills

I have now purchased a new thermostat from Homebase but how do I kno it is suitable for hard water as the area I live in has especially har water. I replaced the immersion heating after only a few months and i was covered in limescale

-- chrisdeehills

I had the same problem with a new stat I bought, cut out all the time.

I then got a new immersion heater that came with another new thermostat from CITY PLUMBING for =A314 or so, and it's been fine since.