Question about Carrier XHB123D X/Y Series Heat/Cool Air Conditioner

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Fan continues to run after desired heat is established , I blew out the line at pilot and the unit is taking 10 to 15 mins for fan to cut off

Carrier natural gas unit
last night it continued to run fan but no heat for about 30 minitues

but today I found that the pilot was so I blew out the gas line at the pilot and relit pilot it heats up and runs but when I cut thermostat down it takes  10 to 15 minutes for the fan to cut off

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Re: fan continues to run after desired heat is...

Looks like your fan limit switch may be bad. It fits into the warm air side of the furnace. It tells the fan to come one and off when the heat is blowing over the limit switch. Now if that limit is defective it also will affect the lighting of your heater being it electronic ig-niter or just common thermocouple type controlled pilot light. Now above your post I think the wong information was given about your gas heater, so giving you the exact information will be difficult. Now from hearing you explanation of the problems, I hope my information was a help to you, Thanks Sea Breeze

Posted on Oct 29, 2007

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