Heating, Air Conditioning, Fridge, HVAC/electric furnace



fan relay
fan relay  
Sears model 867.587240.  Furnace is 33 years old without any problems. I would say it is used weekly, not daily, for 7months per year.  I replaced the original thermostat (Sears #387.914901) with Honeywell RTH2300.(The thermostat has a red and a white wire only).  Do not know if that is relevant to problem or not,but after installation of thermostat the furnace fan will not shut off.  I did not discover this for two weeks as we left for vacation and its when we returned that I discovered it.  Subsequently I have tried everything to turn fan off. Fan stays on even when thermostat has been removed.

I replaced the fan relay (part# 604199)but that did not solve my problem.  The only way I can shut off fan is at the fuse panel.  When I trip the fuse panel on, the furnace fan starts immediately.  There is no delay as when controlled by thermostat. I do not think my problem is thermostat related, but that is why I am asking for help.  The furnace does heat when called to do so.  Otherwise it just blows cool air.  By chance I might have a faulty new relay but again I do not think that is the answer.  

Without your help, my next thought is limit switch.  There are (5)  160deg limit switches.  This seems to be an expensive optionx5 since I would not know which one to start with.  Hopefully I have given you enough details that you can help me. Thank you Pat

Hello Pat,
         Thank you for your request.  Unfortunately our expertise is with Major Home Appliances only.  This site puts Home Refrigeration and HVAC in the same catagory.  This would include washers, dryers, refrigerators, microwaves, dishwasher, ranges and ovens.  If you need help with any of these appliances, feel free to submit another request.  For your problem, please request assistance from a AllExpert with experience in the HVAC service field.  If you ever need assistance with Major Home Appliances feel free to come back and initiate another request.  Visit our Website at http://www.affordableappliance.com or email us directly at sales@affordableappliance.com

Thank You for your request,
Eric & Ann Campion  

Heating, Air Conditioning, Fridge, HVAC

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Eric Campion


We have been repairing appliances for over 36 years and have owned our own business for the same. We can help in any or almost all complaints or at least give you some intelligent input to help you make rational decisions. If maxed-out... You may visit our website at http://www.affordableappliance.com for quicker service.


30 years owning our business and repairing Major Home Appliances

Chamber of Commerce. Better Business Bureau. Pottsville Business Association. EXPERIENCE

36 Years of Working on Major Home Appliances and selling parts. Our office staff is top notched and is supervised by My Wife Ann who is also very experienced in the Major Home Appliance Service and Part Sales Business

My credentials can be viewed on my website at http://www.affordableappliance.com

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