Heating, Air Conditioning, Fridge, HVAC/heat pump/AC Inside unit noise


I have an AC unit in my home.The inside unit is making a whirring noise almost like a something is in the blades of a fan. The air is coming out cool but the sound can be heard through the vents. What is the problem? It just started today.


If you have fiberboard ductwork ,possible a piece of duct came off on your return side and lodged near the blower wheel. Also your return duct(s) must be free of obstructions and the louvers must be clean .  You would have to open the blower door and investigate around the blower wheel, check to make sure the blower wheel free spins and is not starting to bind up. There should be a shut off switch by the fan section to turn power off while you investigate. Your filter may be plugged up also. Your indoor coil inlet side may be extremely dirty, all the above can make a whirring sound. Now if you complained of noise, you would have to check to make sure the blower section is not scraping  ( blower wheel ) or your missing screws, or the blower housing is loosing up. The blower door usually is a 5/16" hex screws

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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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