I have a thermordyne standard gas valve furnace model number M1GB 090A AW. I had this problem for almost 4 years, the pilot light will get blown out after one or two runs, and I have to relight it.
- first i had a technical came in and replace the thermocouple , didn't help .
- had a different tech come in a replace the gas valve , and check all the gas pleasure , didn't fix the problem.
- had the gas company technical came in the check the gas pleasure in to the house and check if the there was crack in the heat exchanger, and both were fine .and he clean out the gas tube and the orifice , that help the furnace run a little bit longer but still the pilot light get blow out few times a day . and also he changed the thermocouples once again.
i went up to the roof and open the chimney and look down with the flash light and check for any routing or anything was blocking the chimney , but the chimney looks perfect clean,there wasn't even a dirty spot or hole in it . i didn't this while replacing the roof .
After all this I started to think maybe the gas valve we changed was bad from the factory , so i had the first Tech came in today and replace a new valve ,brand new from the package. Again he also put in a new thermocoupler, just in case. The problem still remains. Now I'm running out of options, other than putting in a new furnace, which I don't really have the budget for.