Oldiebut goodie wrote:Thermal fuses tend to be used in sneaky applications like in a module that isn't easily dismantable to give manufacturers/service centres the chance to say 'new unit needed mate' ...
Quick test tells you that the windings are gone but if you know to look for that fuse it is a cheap fix!
Used to get that a lot in Hi-Fi / PA / Guitar amps too. More than once I have effected a perfectly safe and proper repair and had the customer amazed and delighted because somewhere else had told them it was beyond economical repair and, as you say, "new unit needed mate" I wonder how many perfectly serviceable items, some quite expensive, have been scrapped because of one of those little tubular type thermal fuses they put in transformers.
Did you manage to establish that it is in fact open circuit(not conducting)?
I am not sure what type of device you have but when you see that sort of thing in a washing machine or tumble drier they call them an overheat stat. & although they are the often the trip & auto reset type I believe they can sometimes stick open & can be reset by firmly banging them face down on a hard surface ( or even throwing them on the floor).
Unfortunately in my experience when they fail they have disintegrated inside, but it might be worth a try.
OK
I finally got round to taking a couple of photos. I also tried to use my multimeter to check for continuity.
I plugged the red lead into the middle socket and the black lead into the bottom one - this is when I get stuck, which setting on the dial do I use to check the continuity of the T24 Thermostat part?
That's odd - if anything I would have expected it to be the other way round! Maybe you didn't touch the probes together firmly enough (usually around 0.2 to 0.4 ohms).
Anyway, it seems that there is nothing wrong with the cut-out so you will have to check elsewhere for the fault.
(I've got 3 new ones sitting on the workbench - 1 is 0 ohms, next is 0.2 ohms and the 3rd is 0.7 ohms, so yours will be OK)
How would I go about testing the switch? Thanks so far BTW
I think something blew when it stopped working last winter. I heard a pop/bang.
The switch has an red LED in it which still lights up. Daft or perhaps not daft question, if I completed the circuit without the Thermostat (just to test), should the heater work if is was only the thermostat that is faulty?
Now I'm learning about how to measure/look for continuity, I check the wire that loops its self back and forth on the wall of the heater (guessing this wire heats up to create he warmth - it does not have any continuity.
um, I wonder if it is easy to replace? It has a foil sheet glued to it and the wall of the heater.
I would ditch the heater then - that is the main heating resistance wire. By the time you have sourced a correct replacement it would most probably be just as expensive as buying a new heater! It sounds as though it is all bonded in position so wouldn't be as straightforward to replace as an oven or kettle element.
I wonder how many perfectly serviceable items, some quite expensive, have been scrapped because of one of those little tubular type thermal fuses they put in transformers.
It sounds as though it is all bonded in position so wouldn't be as straightforward to replace as an oven or kettle element.