Question on ELMWOOD thermal switch on Honeywell water heater

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Probably better to replace the whole assembly. Its alot cheaper than replacing the water heater. How old is theWH?
Could be under warranty.
 
That thermal switch was not always on a water heater and it’s not on all water heaters. It was added to shut down the heater during a flammable vapor burn. It will not extinguish the vapor burn but it takes the water heater offline otherwise.

It usually trips because the heater is starved for air.

Rheem uses an oil vile filled with peanut oil to hold open a spring loaded door that supplies air to the burn chamber. If the burn chamber temp gets too high it expands the oil which breaks the vile of oil and the spring door slams shut. This will extinguish all flame in the burn chamber.

Typically I see the Rheem shut down from lack of air which causes burn chamber temp to exceed the limit.

Bad venting/obstructed can be a cause.

Closing the door to a room that doesn’t provide enough air for the water heater.

The water heater gas control has a one time thermal fuse in gas control that if the water temp exceeds that limit the control shuts down. I believe that shut down temp is 160 or 170, I forgot the number and it may vary a little between manufacturers, I’m not sure
 
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They don’t sell it separately, and the OP just wants that one part. Deadlock. Either the company cares enough about the sale and their reputation that they’ll sell (or, heck, give) him the individual part or the consumer will have to buy the whole assembly. Guess who wins?
there is a reason it is done that way. It's called a sealed combustion chamber
 
Well, that one isn’t sealed so well anymore. Guess that one needs the entire assembly.
Unfortunately, it looks like that over temperature switch has the wires broken off as well, or you could send it to the OP. 😁
 
Well, that one isn’t sealed so well anymore. Guess that one needs the entire assembly.
Unfortunately, it looks like that over temperature switch has the wires broken off as well, or you could send it to the OP. 😁
The wires are fine. It’s just a little bent.

Help me please, I need hot water ! 🤣
 
So did it blow up, or did someone open it with a crowbar?
The tank leaked. So its going the scrapper.

I opened it up and then bent it with my hand to take a pic of the burn chamber high temp limit.
 

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