I have a 4 year old Goodman heater model GMS81155CNA that we just replaced the blower motor on, fortunately it was under warranty until April. Now it keeps trying to cycle 2 or 3 times before the burners actually go on, sometimes it will ignite on the first attempt other times it won't. Often we will have to flip the emergency burner switch to get it running again because the temp will drop in the house and it won't kick on at all. The repairman said it's common of the Goodman's since the glow stick is not mounted in the proper place and is a bit misaligned. Another repairman, over the phone, said it sounded like a pressure switch problem. The heater will also go on for short periods of time and shut off. It reaches the desired temp and when set at, let's say 75, will continuously run till it reaches that temp so I don't think it's the thermostat. Any thoughts or suggestions I can give my handy husband to try would be much appreciated
Heating & Cooling - Goodman - GMS90703BXA Heater
Answers & Comments
I would start by checking the flame sensor mounted in the same area as the ignitor or glow stick as you called it... the flame sensor is a metal rod mounted in the direct path of the flame once lighted... it senses the flame and sends signal back to control board to keep gas valve opened and continue the operation.... if the flame sensor is dirty or faulty will start to shut system down premature... the pressure switch could be a problem as well but normally if it goes bad it will fail as soon as unit fires and continue to fail due to a bad diaphram in switch... will mimic a bad flame sensor as well unit will fire but will within seconds shut back down.... the ignitor has to be hot enough to light when gas enters chamber and can be weak but if it works sometimes then i would say it is ok....the flame sensor can be pulled and gently cleaned with light grit sand paper dont over due it but clean it up a little and try it... again it is located next to hot surface ignitor( glow stick) usually has quarter inch hex head screw holding it in place... positional to get out but will come out....