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Silent Night Electric Blanket- Control unit Repair

Wcripps

New Member
Hi Guys,

Can anyone identify these two blown parts here? I’d like to resolder 2 replacements but as I hate throwing things away. I think they’re resistors but not sure what the wattage. Also if anyone could shed any light and the resistors going pop and the thermal fuse seemingly staying intact that would be cool.

Thanks!

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Ben There

New Member
I have a blanket with a very similar brd. Measure the resistors. I don’t remember the values, but mine were still good and the same value. The problem is the white axial device between them. It is a thermal fuse that opens on over-temp. Measure it, open if bad. Replace it with the same temp for safety. Then, don’t use the blanket over level 2 and it shouldn’t fail again. I went thru this 3x and it’s still working for me. Level 2 is warm enough. My blanket has 4 setting levels.
 

Wcripps

New Member
I have a blanket with a very similar brd. Measure the resistors. I don’t remember the values, but mine were still good and the same value. The problem is the white axial device between them. It is a thermal fuse that opens on over-temp. Measure it, open if bad. Replace it with the same temp for safety. Then, don’t use the blanket over level 2 and it shouldn’t fail again. I went thru this 3x and it’s still working for me. Level 2 is warm enough. My blanket has 4 setting levels.
Thanks I’ll measure the resistors, hopefully they are ok. If the thermal fuse allows a current to pass through does that mean it’s broken?
Thanks again
 

Nigel Goodwin

Super Moderator
Most Helpful Member
Thanks I’ll measure the resistors, hopefully they are ok. If the thermal fuse allows a current to pass through does that mean it’s broken?
Thanks again
No, if it passes current (i.e. near to zero ohms) then it's good - if it reads high resistance (or O/C) then it's blown. The resistors are unlikely to be faulty.
 

Wcripps

New Member
No, if it passes current (i.e. near to zero ohms) then it's good - if it reads high resistance (or O/C) then it's blown. The resistors are unlikely to be faulty.
Ok so the resistors read 1.8k ohms so they are fine. The thermal fuse reads 0 so they are fine. Perhaps the blanket itself has failed then. Bummer. At least I learned something new eh.
 

Nigel Goodwin

Super Moderator
Most Helpful Member
Ok so the resistors read 1.8k ohms so they are fine. The thermal fuse reads 0 so they are fine. Perhaps the blanket itself has failed then. Bummer. At least I learned something new eh.
Where I used to work (an electrical shop) people used to bring electric blankets in for 'servicing' - and we used to send them back to the manufacturer for it to be done.

In every single case they simply said it was too dangerous to repair, and offered a discount voucher against a new blanket.
 

Wcripps

New Member
Where I used to work (an electrical shop) people used to bring electric blankets in for 'servicing' - and we used to send them back to the manufacturer for it to be done.

In every single case they simply said it was too dangerous to repair, and offered a discount voucher against a new blanket.
Well that puts that to bed then, think I’ll buy a new one instead of burning the house down! Also, sad that these companies make things that can’t really be repaired
 

Nigel Goodwin

Super Moderator
Most Helpful Member
Well that puts that to bed then, think I’ll buy a new one instead of burning the house down! Also, sad that these companies make things that can’t really be repaired
Look at the construction of an electric blanket, how do you think it's repairable, without spending considerably more than it costs to buy a new one.

Not that I would suggest people use them anyway, the entire principle isn't very safe.
 

BR-549

Member
Having bad circulation, my electric blanket is a godsend. I keep spares in stock. In the future they might become very popular with all. With the cost and regulation on energy.
 

soother

New Member
Those resistors have been pretty hot. They should be squeezed up tight to the thermal fuse, and there is sometimes a blob of silicone over the top. That fuse should have opened. The resistors are monitoring the current drawn by the blanket, and it looks like there was a fault to cause overheating like that.
 

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