Heating, Air Conditioning, Fridge, HVAC/noise generated AFTER heat is ON



When I turn the heat on, after about two seconds, I hear a lot of noise.  I do get the heat from this CARRIER  (model#58GFA105-12112) series 120.  Sometimes, the noise, as a loud vibration, lessens after an hour or so.  
I don't believe the noise is coming from the DRAFT INDUCER FAN MOTOR but, probably from the BLOWER ASSEMBLY...but, I'm NOT an expert like you!.

NO problem with the pilot, NO FLAME SENSOR NOR SPARK IGNITER on this unit!. Just NOISE after BURNERS come on, as air is pushed upward.  Everything else OK.

What do you think?.

Thank you,

ANSWER: Without hearing the noise, it is hard for me to determine the cause.  You can try setting the fan to on, and see if the noise is there while just the fan is running.  It is also quite possible the noise it caused from the heating and contracting of the unit and or the duct work attached to the unit.


---------- FOLLOW-UP ----------

I had the fan in the 'on' position and, NO noise - so I assume that the Blower Motor is working just fine: no noise is coming from the scroll cage within blower compartment.  Should I assume that the noise is coming from the Draft Inducer Fan Motor - thus, change it?.

I am not sure since I cant hear it.  You can turn off the gas supply to the furnace and see if you hear the noise when the inducer fan runs.  It should try to start a few times before tripping off flame failure.  Just turn the power off to reset and turn the gas back on when  you are done.

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Craig HVAC Expert


I have been in the HVAC field for the past 18 years. I can help with most HVAC questions. I work on commerical buildings for the most part, and have yet to find anything I could not troubleshoot and repair, when repairable. I work on small 1 ton units to a 2500 ton chiller. Troubleshoot air flow, elect, and control problems. I attend regular classes to keep up with the latest and greatest.


I work on commerical sites, hospitals, gov't buildings. I can troubleshoot just about anything in the HVAC business.

5 years trade school, VFD training classes, Liebert factory training, some York and Trane factory training.

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