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Category: HVAC
Satisfied Customers: 15153
Experience:  15yrs in the HVAC industry with certificates and degrees.
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Runs runs aiways, 2days, yes, unit runs great fan keeps

Customer Question

runs runs aiways
JA: I'll do all I can to help. How long have you been dealing with this?
Customer: 2days
JA: Do you plan on doing the work yourself?
Customer: yes
JA: Anything else we should know to help you best?
Customer: unit runs great fan keeps runing
JA: Did you double-check the thermostat? And what about the unit's filters?
Customer: replaced both
Submitted: 11 months ago.
Category: HVAC
Expert:  HVAC Guru replied 11 months ago.

Hello, one minute while I get some information together.

Expert:  HVAC Guru replied 11 months ago.

Hello and thanks for using this service! If you are a JA Member I would like to personally thank you and welcome you back! I am Appliance Guru an extremely experienced tech on the site and I try to get to as many customers as I can. NOTE it takes time for me to type research and add links so please wait for me to respond back I can only do this so fast. Secondly, I do not know your skill level so please try and let me know if I am going beyond your knowledge or comfort zone thanks! I strive for a 5 star rating from everyone especially our JA members.


This is likely a thermal rollout issue if it is running but does not heat. If it is heating fine but just runs check the thermostat and make sure the FAN setting is on AUTO not ON....then if it still happens you may have a bad fan relay otherwise check the high limit safety thermostats that are around the burner housing area that can trip open if they fail or the unit is overheating. Some of these have reset buttons on them that you can manually press down to reset while others do not. The ones that do not either are one time limits or are limits that are suppose to manually reset when cooled down. Now that does not always happen when they go bad so you will have to check them for continuity with an ohm meter across the two leads going to them. If you do not pwn a ohm meter you can physically bypass each rollout to make sure it is good by connecting the two wires to each rollout sensor together to see if the unit will then operate. Now once you have found the bad one you can change it out or reset it and then you should check your furnace filter for blockages and make sure you main furnace blower is running to speed. These two things can cause a unit to overheat and trip one of these rollout sensors. Mosts units have 3 of these devices and here is a link to what they can look like on your unit.




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