This is becoming a more frequent problem. Erratic behavior in that the furnace canbe working well and the next time the thermostat calls for heat,the valve does not open and therefore, no gas to the burners. The blower will execute and run and run and run until someone discovers the temperature is falling in the haouse and there is no heat coming from the registers.
By simply turning the thermostat from on to off, and then turning it back to on, the pilot and gas valve will now open and gas gets to the burners and heat is produced.
Has anone experienced these same symptoms. Repairmen have found no problem in each cursory review, no complete diagnostics have been run at this time.
Arcoaire and is approx 13 years old.