Heating, Air Conditioning, Fridge, HVAC/Bryant plus 90, Model # 398AA


My furnace works great on heat, but on cooling the compressor works and the pipes get cold, but the blower never turns on. What is the possible cause?

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Try placing your fan switch at the stat to on from auto your blower should run 24/7. If it does, then while your in A/C mode and fan in auto and calling for cool you would need to check the voltage at the fan relay coil, should have 24 volt ac. If not you need to backtrack, look at the wiring diagram , your stat may be bad. You can remove the G wire at the stat and place it on the y terminal. ( The y terminal brings on the compressor contactor ).If the compressor comes on and blower fan works OK chances it's your stat.If this is a regular multispeed motor and your fan relay coil is energized and the fan does not start you either have a open cool motor winding or the fan relay high voltage contact is not closing and starting the blower.

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40+ years diversified experience.An HVAC/Refrigeration Self Employed Contractor since 1986. NATE Certifield. Answer questions pertaining to Residential and Commercial Air Conditioning , Warm Air Heating, Heat Pump systems.Mechanical and Electrical troubleshooting of these systems.Be as detailed as possible when describing problem.Packaged unit or split systems.No appliance questions.


Installation and Troubleshooting, Mechanical and Electrical, in following areas, Refrigeration ( Walk In and Reach In Coolers and Freezers ) Commercial Roof Top and Packaged Heating/Cooling ( Natural Gas,Propane, Electric, and Heat Pumps ) Computer Room Air Conditoning Systems,Commercial Residential Packaged and Split Systems Air Conditoning and Heat Pumps.Warm Air Oil , Natural and Propane Gas Heating systems.

Graduated from Private Technical School in 1975. An HVAC/Refrigeration Contractor . Have Unlimited Heating/Piping and Cooling Contractor License.Limited Sheetmetal Contractors License.NATE Certifield. York Certifield Master Heat Pump Technician 1986. Served 33 years combination Active Duty Air Force , Air Force Reserves and Air National Guard in the HVAC/Refrigeration Shop/Mechanical Shop. Troubleshooting/Installing HVAC/Refrigeration Equiptment Worldwide. Retiring in 2003 as a Senior NCO ,and a Mechanical Superintendent.

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