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Old 11-10-2010, 04:52 PM   #1
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limit switch

I have a 1970s carrier ac/gas heater on roof of house, model# 48DL004, series#300, serial# H252538. During the summer blower motor burnt out, I replaced motor and ac worked fine. Now it is starting to cool down for winter, heat does not come on, traced problem (maybe) to 3" hi-limit switch, went to parts store, was told that this part is obselete can not get one, is there a way to by-pass switch to get heat into house?


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Old 11-10-2010, 04:56 PM   #2
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Post a pic of the limit switch. Carrier is pretty good at having parts, probably need a different parts house. NO you cannot bypass it /major fire hazard/void house insurance etc.


"Cut it twice and it is still too short".
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Old 11-10-2010, 06:38 PM   #3
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Never bypass a limit control!!! You could wake up dead!!!
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Old 11-10-2010, 09:04 PM   #4
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A limit that has never opened, doesn't go bad. So your limit has been opening. And saving your house from burning down.

Might want to find out why it has been opening before you replace it. just to have the new one go bad.
Its is around 40 years old. So your heat exchanger could be cracked.
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Old 11-11-2010, 06:57 AM   #5
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1970's. It's time to upgrade & save some $$$$$ on the gas bill
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