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Bad thermal fuse in can light?

weatherby460

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I have a bad thermal fuse in a can light. Since I am replacing the bulb to LED, can I just bypass it? I'm not sure if I can easily find a replacement fuse.

Thanks
 
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cybrdyke

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can I just bypass it?
Is it covered by insulation? If so, move the insulation at least 3" from the downlight.
You shouldn't bypass it. It's there to prevent fires.
LED bulbs can get hot, too.
Another option is to retrofit the can to an LED insert or to a snap-in light. Either of these retrofits will bypass it.
Good luck,
CD
 

Bert_

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An led can put just as much heat into the housing vs an incandescent.

Most of the heat from an incandescent is radiant which heats up things UNDER the light. All the heat from an led is convective and stays in the housing of the can light.
 

cybrdyke

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An led can put just as much heat into the housing vs an incandescent.

If you're using comparable products, no it cant.
A 650 lumen incandescent creates about 58 watts of heat. And that heat rises, it doesn't radiate downward. That's the reason for the big metal dome in the first place. Put your hand on top of a can light after it's had an incandescent bulb on for an hour or so...
A 650 lumen LED creates about 3 watts of heat at the most. Certainly not enough to be concerned about.
CD
 
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Bert_

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If you're using comparable products, no it cant.
A 650 lumen incandescent creates about 58 watts of heat. And that heat rises, it doesn't radiate downward. That's the reason for the big metal dome in the first place. Put your hand on top of a can light after it's had an incandescent bulb on for an hour or so...
A 650 lumen LED creates about 3 watts of heat at the most. Certainly not enough to be concerned about.
CD

Anyone standing underneath an incandescent reflector lamp will feel warm. That's because the lamp is giving off radiant heat, it does not stay in the can. I don't mean to say that all the heat is given off in this way, obviously some of that heat does rise and heat up the can.

I think we can both agree that almost all the heat produced by an led in a can light will stay in the can. Now I haven't measured any temperatures but I have seen many led reflector lamps that run hot enough to burn your hand if held for more than a few seconds.

Led's make more heat than most people realize, getting rid of that heat is actually a major problem. Some larger commercial down lights even use fans to get rid of heat.
 

nadogail

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I once took an HVAC course and recall the instructor telling us that lighting heats up at 2.5 BTU per watt.

He may have been mistaken on the details, but I agree on the concept; high energy equals high heat. The heating element in the od "Easy Bake Oven" was a 100 watt light bulb.

I once worked for a department store where the lighting and the human occupants were the sole heat in the building. They had lots of Air Conditioning.

The reduced energy consumption of LED lighting will certainly generate less heat.
 

cybrdyke

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Anyone standing underneath an incandescent reflector lamp will feel warm. That's because the lamp is giving off radiant heat, it does not stay in the can. I don't mean to say that all the heat is given off in this way, obviously some of that heat does rise and heat up the can.

I think we can both agree that almost all the heat produced by an led in a can light will stay in the can. Now I haven't measured any temperatures but I have seen many led reflector lamps that run hot enough to burn your hand if held for more than a few seconds.

Led's make more heat than most people realize, getting rid of that heat is actually a major problem. Some larger commercial down lights even use fans to get rid of heat.

There simply isn't enough heat created by a 15w LED lamp or insert in a 6" can to be of any concern. Maximum 3 watts would be emitted as heat, if even that much. Even if, as you say, it all stayed in the can, it's of no concern. You can grab a 15 watt bulb that's been on for days, and it's not hot.
Most new LED downlights are rated for use with contact of combustible material (insulation) because of the cool running nature of the product. There is no heat issue just by the nature of their design.
Yes, Back in the day, some high ceiling cans used fans. But the fans were not used to get rid of the heat from the can. They were used to cool off the diodes because the thermal engineering of the array was crappy and the diodes would burn up without active cooling. But the fan wasn't there because the can got too hot.

CD
 

Bert_

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Well, I guess I have to admit I was wrong. I measured the temp on a 19 watt led flood lamp and the lamp didn't get much more than 100 degree's, a little more than 35* above ambient. The can was lucky to hit 70. I remember dealing with a few lamps that ran hotter but obviously that was an exception to the norm.

In comparison a 70w bulb ran around 200*, with the can housing around 100

Measured with a little point and shoot IR thermometer.
 

Brian_WK

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I have can lights that are LED that came housing and LED in one box. They are IC rated and still have the Thermal cut out in them. Just because the LED light when running correctly is only putting out 100F temp doesn't mean that A. The LED will fail and create a over temp situation or B. Someone might screw in a non LED bulb into the socket at some point.

Brian
 
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