Immersion Heater Thermostat mis-calibrated?

[andy]

Well the title is probably wrong but I couldn't think of anything else :o)

My problem is that although I think the thermostat works (water doesn't boil) even if I set it to it's lowest temperature the water still gets very hot, I estimate around 60 degrees, certainly enough to scald.

I am beginning to wonder if the problem is that the stat rod seems a very loose fit in the pocket tube (terminology?) and I am wondering if it just isn't making good enough contact to warm up enough to turn off at the right temp. I asked in a plumbers merchant if there were different diameter stats and I was told there all the same, is this true.

Lastly can you put some sort of oil in the tube to make good thermal contact with the stst or something?

Any help gratefully received.

[Peter Andrews]

1. If you have a multimeter you can test it by putting it in a kettle of cold water and bringing to the boil - it should go open circuit at about the time you can't keep your hand on the kettle!!
2. Replace the thermostat - they are less than £5. Note that some are hottest when turned anticlockwise - colder when turned clockwise. Don't put any lubricant in with it, the air temperature in the sleeve will be very, very close to the water temperature.

Peter

[andy]

Thank you Peter, sorry for the delay in replying I've been away. I will follow your advice and probably replace it.