Why the Pilot Light Keeps Going Out on Your Furnace

Relighting the pilot may bring the heat back, but it does not explain why the flame disappeared in the first place. If your pilot light keeps going out, something may be interfering with the flame, the gas supply or the safety device that monitors it.

This applies to older furnaces with a standing pilot: a small flame that stays lit so it can ignite the main burners when heat is needed. Many newer furnaces use electronic ignition instead. If yours has no standing pilot, the absence of a continuous flame is normal. We can identify the ignition system before investigating the fault.

A Faulty Thermocouple Can Mean the Pilot Light Keeps Going Out

A thermocouple is a safety device positioned where the pilot flame heats it. That heat produces a small electrical signal that allows the gas valve to keep supplying the pilot. If the flame disappears, the signal drops and the valve shuts off the gas.

A worn or faulty thermocouple may no longer produce the necessary signal, even when a flame is present. Incorrect positioning can also prevent the flame from heating it properly. The result is a pilot that lights but will not remain lit. If the flame goes out when the pilot control is released, the thermocouple is one component we would investigate. That symptom does not confirm that it needs replacing. We also need to check whether the flame itself is strong enough and correctly positioned.

A Dirty Pilot Opening is Producing a Weak Flame

The pilot receives gas through a small opening. Dirt or debris restricting that opening can reduce the flow and create a weak or irregular flame. That flame may go out, or it may fail to heat the thermocouple sufficiently.

This means a pilot assembly problem can resemble a thermocouple failure. Replacing the thermocouple without checking the flame may leave the original issue unresolved.

An unusual flame deserves attention, particularly if it is mostly yellow or orange rather than steady and blue. We can inspect the assembly and determine whether cleaning, adjustment or a repair is appropriate. Avoid inserting anything into the pilot opening or adjusting gas components yourself.

Drafts or Gas Supply Problems Are Disrupting the Pilot

A strong air current near the furnace can disturb or extinguish the flame. However, blocking ventilation openings to stop a draft can create another problem. Gas appliances need the combustion air and ventilation specified for their installation. Insufficient gas pressure or a malfunctioning gas valve can also prevent a stable flame. Having problems with your heating system? Call the Hydro-Flo team for furnace repair in Edmonton.