Furnace shutdown have interthern heat/air unit , last spring it started shutting down and blowing out the pilot. had a serviceman out couldn't find anything wrong said the firebox looked ok but needed a new unit. later i found out if i leave the front cover off the furnace ran just fine . had two servicemen look at it & couldn't find anything wrong , big bucks for nothing , HELP! TB

When you say the the furnace re-starts 8 times before shut down, what is cycling 8 times? just the indoor blower or is the main burner re-firing 8 times? If it's only the fan it sounds like the fan control.

Try cleaning the thermocouple tip if you can see ashes or any buildup on it. If you know the wind isn't blowing it out (had mine blow out from high winds before) then I would change the thermocouple before anything else.

You would smell the gas, so you're probably ok. Lighting the pilot is not too tough, first you have to get the cover off the furnace. Inside you will see pipes and parts. Hopefully on the cover, inside or out, or somewhere inside the furnace will be instructions.
If not, find a knob that has 'pilot', 'off' and 'run' or something like that. It will probably be in 'run'.
Usually, you have to push the knob down and turn it to get it to the 'pilot' spot. When you do, have something to lite the pilot, which will be inside the furnace more, near the burner. The burner looks like a gas stove or oven burner. The pilot place will be at the end of a small tube.
With the button held down, wave something burning around the burner area. especially at what may be the pilot. The pilot doesn't put out much gas, so don't worry about things blowing up.
Once the pilot has lit, hold the button down for a while, at least a minute. Then you should be able to release the button and the pilot should stay on. If it doesn't, you need a serviceman to come. Let the landlord know the pilot would not stay lit.
If the pilot stays lit, move the knob to 'run' or such, and the furnace should lite, if the thermostat is set higher than room temp. If it has been off, and the room is cool, it should lite.
If the furnace doesn't come on, let the landlord know.
Most landlords have service people for this, it was my job for a long time. Lighting pilots was a common chore for me. If you can, have the landlord send one out to show you how to do it.
As you see, it's not all tough, but it's not all easy, either.

possibilities are many, no spark due to ng ignitor, if draft induced , fan not coing on or has blocked flue, if unit is condensing type might have condensate in drian line, if standing pilot type thermo couple bad so not sensing pilot. so you see not enough info of what type unit you have to help narrow down possibilities

change fan motor capacitor. the other issue could be low gas pressure. mine acted that way when i was running low on propane.

The tech that fixed the gas leak had to shut the main gas supply off so if he didn't bled the line to the furnace you may still have air in the line....... Go ahead and shut the furnace off and retry to start it again it takes a couple of trys to bled the air out through the pilot.... And if that doesn't work I would call the first tech and have him recheck it......that is assuming that you have an electronic ignition type furnace.

Not sure what type of furnace you have but here a a few easy tips:

How to diagnose Robertshaw electronic pilot ignition

common furnace problems
Thermocouple operation
How do I light the pilot?
Transformers and Thermostats
Electric Furnace Notes
Millivolt valve/ pilot generator/thermopile operation
Wall thermostats



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If the unit is newer than 10 years I guess there will be no pilot light per sey. You will have to look at it to tell for sure. Here it is supposed to work. When there is a call for heat the thermostat will close and send a signal to the furnace to start the exhaust blower. When the blower gets up to speed, it closes a pressure switch that will send voltage to the gas valve and to the igniter. The igniter glows or sparks lighting the pilot. Once the pilot lights it sends a signal that all is well, then the gas valve opens up more and the burner(s) light. There is a sensor that tells the control board when the flame has stayed lit. Once that is done, after a period of time or as the heat exchanger gets to a specific temperature, it will turn on the room air blower and blow hot air. Once the thermostat has been satisfied, the furnace turns off. Now, get in front of the furnace and with the door panels off (you may need to tape down the door safety switch to make this work) watch the furnace go thru each step I described. Once you see where the problem is, you can start the proceed of repair. There may even be a flashing light indicating a problem. Find the wiring diagram on the furnace and look for a diagnostic chart and compare the number of blinks to this chart.

What type of gas supply line do you have? Is it black pipe or copper? If it is copper, there can be a film like substance that builds up on the inside of the copper. The debris will the get caught in a pre screen where the supply enters the valve thus cutting the supply of gas to the unit. Also, the thermocouple may be bad. You didn't say that you replaced it. Try replacing it as well. Also, you could have a limit switch turning the system off and thus cutting the gas off completely but it is highly unusual for the pilot to be cut off as well unless the pilot is being blown out when the gas is shut off. Also, turn the unit to fan only without calling for heat. Using a flame of some sort, put it into each baffle of the heat exchanger. If your flame is being blown around in one of the baffles, then you have a hole in the heat exchanger and what is happening is that the roll out switch is cutting the unit off and the air still moving through the heat exchanger is blowing the pilot out. I have seen this actually happen. If your furnace is in excess of 15 years old, it does need to be checked for possible holes. If it is in excess of 25 years old, it is a huge possibility that the unit has already developed a hole. If you feel hair coming out of one of the baffles, then shut the unit down immediately and have it replaced!

I'm a little confused by your terminology. You are saying you have a pilot lite and electric heat strips? Are you possibly meaning burners? Is the heater running for 2 hours straight without shutting off? how cold is it there? Lastly what temperature do you have the thermostat set at and how close does it get to the temp. before it shuts off?