Need an electrical pro. Thermal Fuse Replacement

[ZekeTheSneak]

Hey guys cold winter here in washington. In my Garage I have a stelpro 5000 watt 240v ceiling mounted heater. Long story short I tripped the thermal fuse again. The garage is around 700 square feet with 10' ceilings. The heater can hang when the outdoor temp is above freezing but the 25 degree weather we had this morning I needed the Propane heater.

I cranked the propane heater up and left the stelpro running as I usually do. I usually kill the propane heater after a few minutes and let the Stelpro take over, which manages just fine. The thermostat for the Heater is about 6 feet off the ground and therefore I set the temp lower to compensate.

Last summer I installed a single ceiling fan which drastically improved the heating. The stelpro was getting stagnant heat up top and the thermostat would not turn off. This burned the thermo fuse the first time around. Since installing the ceiling fan I have not had any problems. Until today.

Stelpro has a good warranty service and sells the fusable link but only through there website. I was wondering if anyone makes a thermo breaker that resets or some other option so I don't have to keep replacing this when It gets too hot? I figured the breaker would trip long before. I have a 20 amp breaker in there currently.

The Fuse in there now is a 84C, Amazon sells these but do they make one that is self resetting?

https://www.amazon.com/dp/B00JVBC160/?tag=atomicindus08-20

 

[rlitman]

Yes, such devices do exist. However, altering the safety mechanism of that heater will void the UL listing, and you can end up in hot water if you burn your garage down.

I'd put a slightly lower temperature resetting thermostat in series with a replacement fuse. That way, it shuts down before the fuse burns out, but the fuse is still there for safety.

This is 75C (might be too cold):
https://www.amazon.com/dp/B07LBK2HDC/?tag=atomicindus08-20

This is 80C (might let your fuse burn out):
https://www.amazon.com/dp/B07CKT4G8P/?tag=atomicindus08-20

 

[ZekeTheSneak]

It has one of those built in already, it measures the coil temps though and I would have to open it to see the temp rating. Maybe that has failed and that's half the problem right there?

 

[Jim greengo]

Where is the thermal fuse located,is it supposed to be some kind of limit that resets itself when it cools down?

 

[ZekeTheSneak]

It's a onetime use thermal fuse. It protects the whole unit from exceeding 84c. IIRC it is on the 120v for the heater circuit. I'm about to pull it apart and look since I have some free time.

 

[ZekeTheSneak]

It's a 240v circuit. It is set up parallel. 120v black leg to thermal fuse where it splits power to heater coil and the fan. The white 120v leg goes to the resettable Thermo sensor then it splits power to fan and heater coil. I'm going to test the disc thermal sensor right now.


Edit. It is a 150degree farenheight thermal disc. I heated it with a heat gun until it clicked and measured the temp with my multi meter. It read way high like 200. I let it cool down and tryed it again and it tripped at 150 degrees like it should. Maybe it's lazy?

 

[Jim greengo]

Do you have a picture of it?

 

[ZekeTheSneak]

2019-02-05_04-13-51 by ZekeTheSneak, on Flickr



This is the 84 degree Celsius fusable link. Located under the white silicone shielding. You can also see the thermal protection for the coils which is rated at 150 degrees F. Whats weird is that the fusable link is failing before the thermal disc. Each of those Posts are where the Black and white romex connect to. Each leg having one version of thermal protection. 20 amp breaker with 10/2 romex. External cheap honeywell thermostat.




2019-02-05_04-14-04 by ZekeTheSneak, on Flickr