I have a baso L62AA-5 pilot switch and it used to keep resetting. I would hold the switch down for a good minute and the gas lights, but after a half an hour or so it would go back to its reset position. The standing pilot light was always on and never a problem.
After a few days of manually starting up the pilot switch, now what happens is the pilot switch doesnt even engage. I cant get any flames unless I put the gas valve to manual. thermostat is set up high so i know thats not an issue. Possibly the thermocouple but how could i be sure. Any help would be greatly appreciated.. im freezing my butt off.

hvac1000

More than likely the thermocouple. It is the cheapest part to replace. make sure you have the to 3/4 inch of the new thermocouple into the flame.

It is possible the old style baso has seen better days they are still available but not real popular. You might consider going to a 24 volt valve set up. It is much better and safer than the baso because it gives you 100% safety shutoff.

aznwho

Hmm i actually just tried to light it up again and it fired up, but after a few minutes it shut back off again. I looked at the end of the thermocouple and it doesnt even look like its sitting in the flame. It looks like its going vertically straight up next to the flame but not touching. Is it supposed to be bent inwards to sit right in the flame? If so then I could probably bend it into place?
Thanks for your help hvac hopefully i can get it to work before i sleep. its getting quite cold

hvac1000

Actually you should not have to bend anything. If this thermocouple has wires on it it is not a thermocouple but a milivolt generator and that is a little different ballgame. if it is a regular thermocouple it should be about 3/4 inch into the flame. You might also have a dirty pilot orifice not allowing the flame to spread to the thermocouple.

aznwho

its just a regular thermocouple. it was kinda loose on the pilot flame end so i adjusted it and now the thermocouple sits better in the flame. seems to be working well for now. again thanks for all your help. now I can sleep nice and warm. =)

also if you dont mind can i ask you a couple more questions?

i wanna know if the pilot flame is supposed to stay on even when i shut the gas valve off, because i shut it off before for like 20 seconds and the pilot flame was still on.
If it supposed to stay on can I just blow it out because I may change the thermocouple if the problem reoccurs.

hvac1000

Your system is not 100% safety shutoff. That means if you just shut off the main gas valve it may not turn off the pilot. Follow the pilot tube back to where it connects for its gas supply. usually there is a very small finger shut off valve there to kill the pilot gas. One way or the other there has to be a way to turn the pilot gas off just look around and you will find it.

BY just blowing out the pilot flame is not a good idea. It will just allow the pilot gas to accumulate in the furnace and when you go to relite the pilot it might go BOOM. LOL

Note I mentioned before that a 100% shut off system is available. In the future you might consider changing it over for better safety.