HVAC Repairs in Cary, North Carolina
Diagnosing and repairing Honeywell gas valves. Sometimes gas valves start to stick and do not operate fast enough to allow the other sensors to tell your furnace everything is working properly. Therefore the furnace shuts down and goes into lock out mode.
Here was a unique situation where the furnace had an intermittent problem igniting.
Sometimes the furnace would run fine then other times it would not turn on. What we found is a sticky gas valve. If the furnace had been idle for several days, the valve would be extra slow opening and the circuit board would go into lockout for no flame sensed. Then if it had been cycled several times, especially cold nights, the furnace would work fine. This was because the valve was moving more frequently and not sticking as much.
Replacing the gas valve was the solution.