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I just moved into house 2010 Goodman gas furnace, HVAC man says duct work reversed. Old wood/coal moved out, gas furnace moved in. Impossible for me to believe that it was installed wrong, intentionally or unintentionally. Leaves possibility motor was reversed thru surge?
House sits beside three sewer lines of long runs to main. Electrical accumulation source? HVAC man says furnace not grounded. Sited downhill so always has water in ground around basement. Basement walls but not wet floor.
Am not engineer or even informed. Just guessing. Something has to be wrong, what?
katesisco@yahoo.com
218 590 4549 text

I have never heard of a motor being reversed by a surge. A surge is usually just a momentary over voltage. Either it would just not do anything or it would damage or destroy the motor. Most HVAC fans are squirrel cage design. One of these running in reverse would not put out very much air. The furnace not being grounded is just a safety factor and would not cause a surge. My thought is it was either intentionally or unintentionally installed wrong.