Why does the pilot light on my furnace keep going out?

The boom indicates delayed ignition of the main burner.

This could be caused by a low pilot or a dirty burner. This could also be why your pilot goes out intermittently.

If you have a pilot that is on all the time it will have a thermocouple and it should be replaced every few years.

Call a service tech for a check up, this should be an easy fix.

Relighting Furnace Pilot Light

genereally any furnace that still has a standing pilot this day and age is rougly about 20 years old. standing pilots will go out from either a downdraft effect from your chimney (cold air entering through chimney), or excessive air.

as a heating contractor myself, I never simply re-light the pilot, or replace the thermocouple (part that holds the pilot) and leave. I always question WHY has the pilot gone out...

If it's been a problem since day one, you may have a venting issue. This is highly unlikely the case. You seem to only be having this problem recently...which will lead me to this diagnosis:

your 20 year old furnace is receiving excessive air, causing your standing pilot to blow out. The excessive air is most likely coming from a compromise in your heat exchanger (core of the furnace - barrier between your products of combustion and air that you breathe).

Have a qualified technician to come out and have a look at your furnace, the pilot blowing out may be the least of your worries. If your heat exchanger is in fact found to be defective, you are suceptable to carbon monoxide poisioning (carbon monoxide is a colorless odorless tasteless deadly gas).

The "boom" you heard was most likely a "flame roll out" which is yet another very good reason to have your furnace looked at by a professional. This is potentially an immidiate hazard and the service tech may even condemn your furnace.

When you're cold you do not want to wait to re-light the pilot. I know I have been cold (14 below) so its easy to forget to TURN OFF THE GAS FLOW. LOL You need to let the air clear for at least 5 minutes before relighting the pilot light. Even the gas from the pilot can create a tiny proof if the gas builds up there. Did you ever as a kid take a BIC lighter and fill your slightly opened fist by holding down the button on the lighter then striking the lighter next to the opening of your palm? It makes a little fire ball in your palm, mostly harmless & kinda cool looking, same principle. ( don't try that it was a stupid thing for us to do.) Anyway, You probably have airflow blowing out your pilot light. Check for doors that causes breezes in your home when they open & shut. If there are any cracks near the area of your pilot light then you can find them by lighting a candle and slowly going around the room & near windows when your flame flickers wildly you know there is wind & you should block the crack with foaming sealant ($4 per can), duct tape or even a folded cloth or sock until you can fix it properly. This is for like walls, windows & door jams not breathing cracks on the heater itself. if you find a crack on the heater itself you can use metal flashing tape to protect the pilot from being blown out. Do not close up any manufacturers openings because they need to be there. Another reason the pilot might be blowing out is it might be slighty blocked with soot. Turn the gas off and use a dry clean tooth brush and buff the top of the pilot light then blow off the residue before relighting the pilot. Depending on how old your unit is will help you figure out if the pilot needs to be buffed. Really though it is most likely getting blown out by airflow.

Good luck,

Terri,

Is funace in a drafty area? Often this will cause pilot to go out. You might also consider replacing the thermocouple, they are cheap enough. As far as the boom, next time pilot goes out, shut off the gas supply with the little red knob, and leave it off for an hour, before attempting to relight.

sounds like the pilot light might be dirty,,not burning well enough to light the burners quickly once gas is flowing to the burners....thermocouple could be weak and in need of replacement but that wont cause the "delayed ignition" you described..delayed ignition is caused by a dirty pilot,,dirty burners,,or,more rarely, low gas pressure to the furnace/home...you might be able to get a free diagnosis from your local gas utility,based on the delayed ignition complaint.......dan

it could be that there is something wrong with your hot water tank thingy, but to be sure you might want to call a repair person to repair it in which case they will probably send some guy out that isn't very attractive and he'll probably have breathing problems and want to talk a lot about his job and other people's problems that they have had with hot water tanks or it could be that they'll send some good looking hunk out to repair your hot water tank and he'll have a beautiful tan, his sleeves rolled up, pearly white teeth and a little bit of chest hair peeking through the top of his shirt and he'll know everything about everything and have that boyish grin and he'll probably be one of those repair guys that looks you straight into your eyes and you'll notice how blue his eyes are with those dark black eye lashes he has and he'll touch your arm to lead you over to the hot water heater to show you something and you'll almost faint and then he'll help you to your day bead so you can recover while he repairs your hot water thingy...and inspects the rest of your plumbing to make sure it's safe....

Oops! You'll want a repairman to take a look at that!

There might be a leak in your line, or the light might be clogged.

More often than not it is the thermocouple