Originally Posted by Jeffthrow

I have the same exact problem, seems the switch to light the pilot(on Honeywell gas valve) may be failing me. Been acting up for a while now, when I depress the switch everything fires up flawlessly.. I turn the switch to on and no matter how long or little I hold it in, entire system powers down. After much research and studying of what i have (thermocouple, ignighter, and pilot seem to perform great. The Pilot switch? seems to be very loose as if its tripped off.
Basically i can clamp switch in the on posision, depressed slightly furnace and thermostat run flawlessly but obviously do not think running it this way is safe so I do not.. sometimes I can get it to work for days after holding it down forever and releasing ever so carefully.. sick of the cold nights and times are tight to make a worthless payment to a pro to troubleshoot for days on what I know works fine.
Can this be Fixed by opening up the gas valve, common problem??