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Phil
Phil, Mechanical Engineer
Category: HVAC
Satisfied Customers: 5648
Experience:  Retired HVAC/ Electrical & Boiler contractor. Industrial
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I have a Goodman GDS80703ANA that has been giving me

Customer Question

I have a Goodman GDS80703ANA that has been giving me trouble. After much troubleshooting I have determined that the unit starts and runs fine when cold. After the unit is heated up, (aprox 6 or7 min) the gas will shut off without the thermostat reaching temp and the blower will continue to run. However, when the unit tries to re-light, the gas valve will not open. after three tries the system shuts down and I get a single flash on the LED (re-tries exceeded). If I power down the unit and let it cool down and turn it back on, sometimes it will run for a day or so, but it eventually dose it again. I also noticed that it seems like the gas-flow is higher than I remember (flames look bigger and have more orange to them). PLEASE HELP!
Submitted: 1 year ago.
Category: HVAC
Expert:  Phil replied 1 year ago.

Hello, Orange in the burner flames is a red flag, it indicates too much fuel and not enough air going to the burner heads. That aspect need to be looked over on site by a qualified HVAC technician who owns combustion analysis equipment.

The other issue, early termination, and three tries at starting up etc. Point to a dirty flame sensor, probably caused by soot from the yellow in the burner flame..

The fact that you have to wait until the furnace turns off sometimes before it will restart points to air distribution duct work too small, or a dirty air filter or something else blocking the air flow... that causes the high temperature safety limit switch to trip.

Look all that over, take your time, clean the flame sensor rod with steel wool...you can find it on the wiring diagram, then follow the wire to it from the printed circuit card...all you will see is two screws holding a white ceramic insulator in place.

Let me know what you can discover, we can go from there without a time limit.