Comfortmaker blower intermittent problem
I have a 1990 SnyderGeneral Model #GUA100 Comfortmaker furnance that has developed a problem. The blower will not start when the furnance heats up. The furnance will ignite and simply runs and runs, but the blower will not start. The blower has been replaced but this still has not corrected the problem. Recently when the furnance has been runing I manually switched the fan on at the thermostat. While the fan is running the blower starts a few minutes later. I switch the fan off and most of the time the blower continues until the furnance has heated to the setting temperature. When the furnance trys to recyle again the blower will not start and I have to manually start the fan again.
At no time does the error light come.
Any help, and all suggestions, are greatly appreciated.
Could be a weak capacitor, but the motor uses the same capacitor for hi speed (fan on) and heat (low speed).
If you can force the fan on at the t-stat then I would suspect the fan relay.
Does this unit have a fan/limit switch or a relay? Why was the blower replaced?