i have a gibson furnace about 5 years old. have had lots of trouble with it. this time we have no heat again i checked the leds and found red light is on constant. looked at code and it says false flame or gas valve shorted. i turned off power and waited 5 minutes it did nothing and red light stays on constant.i pulled wire from flame roll out switch and it will turn on all fans but no ignition cleaned flame sensor and still no luck. also checked drain lines and presure switch. what should i try next im a diesel mechanic.
had it been running for heat and it crapped out? things to check 24Vs off the Main Transformer 24Vs at the control board within,filters ..can you swittch to FAN/ON at the stat if you have cooling also...just want to see that supply fan run from the stat!if it was running the gas valve might of shorted...get a meter shut power and with the OHMS setting remove the wires off the gas valve check for continuity on the coil for the valve....if it shows resistance cool..reconnect restart and see if you see 24V go to that valve.do you have a Induced Draft motor mounted on the burner section that pressurizes the burner chamber? if you do that should run first when the stat calls...then that 4'round disc with the orange tube going into it should close telling the gas section air is being supplied into the burner....spark...pilot...then main gas burner....any reset buttons for the draft or roll out there....that resistance reading on the gas valve coil...if it is showing open like your holding the leads in each hand...the coil within it is shot....as this 1.0