Gas and Oil Home Heating Furnaces - HEATER LOCKOUT

I have a York model. System was just cleaned out by technician last month. Woke up this morning feeling a little cold. The one light was flashing signalling a LOCKOUT. When I shut down the system and restarted, all sytems run fine except NO FLAME. It retries itself before lockout. How do I fix this problem???

Try reseting the rollout switchs. They are about dime size with a red button in the center. They are located around the burner area. Usually York has three. One on top of burner shroud and one on either side. Also some have the same type of switch located around the flue area. Call back the company that did the service, you may really have a problem, that was not caused by it being serviced. Your problem is not as easy as you may be hoping, even if the resets start the burners.

Usually a lockout occurs due to: 1. Failure to ignite 2. Furnace ignites but flame is not sensed. 3. Furnace is firing & Flame signal is lost 4. Flame is sensed when there should be no flame. 5. module self check finds a flaw in itself 6. limit or rollout switches open. 7. module senses a loss of combustion air Look closely at module, unit data sticker, & any accompanying paper work to see if it lists a series of LED flashes & what they indicate. Qequence of operation must be observed to garner clues to problem. Sequence is: !. tstat calls for heat. 2 Module checks combustion air switch to see that it shows no blower operation. Then blower is energized. It then checks the switch again & this proves combustion blower is working & that air switch is functioning. It sounds like up to here you may be okay. Next event is to have a 17.5 second heat up time fo the igniter. It should glow like a lightbulb shortly. If this does not happen, cause may be failed (cracked) igniter,failure to prove combusion airflow, open limit/rollout switch, or defective module. If igniter glows the at end of 17.5 second heatup. Gas valve is energized briefly. Module has 1/2 second to "prove" flame or it will go into soft lockout. So if it lights & immediately goes out, them module did not "see" the flame. If it ignites next step is for the blower to time on. & you should be heating.