Heating, Air Conditioning, Fridge, HVAC/Forced air gas heater


Steven wrote at 2013-03-18 08:28:29
I have the same model furnace and it started making a rhythmic banging early this morning.  It starts about 4-5 minutes into burn cycle, is lower than the rice krispies, more like a hammer on the duct work.  It's fast, even, about 4 beats per second.  Flames look good.  I haven't let it run its course to see how long it lasts.  I lowered the thermostat so the furnace would shut off.  But the banging continues until the burners turn off.  The blower cools down the bonnet and the unit shuts down.  What's going on?

Heating, Air Conditioning, Fridge, HVAC

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Jim Barnhart


Fifty + years conditioning the air.


Answer questions about , residential and commercial. Answer questions about sheet metal fabrication. Fifty years plus experience. No answers for oil equipment, No answers for kitchen appliances, No answers for laundry appliances, I don't specialize in one particular area of the HVAC area, I'm more of a General Practitioner, Limited in refrigeration/

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