My Payne is being a pain. Payne Model PG9MAA036060ABKA (1998) How likely is it to find a HSI that gets hot enough to open the gas valve but doesn't ignite the gas? Especially if its old? I cannot confirm either way if it is the original HSI or if/when it was last replaced. I've tried HVAC repair but the problem is not often repeatable, and when they get there it's either already running, or when they reset it to watch it works just fine. It wasn't until today someone(me) got a first hand look at it failing to light, albeit just once. Have a furnace that's been going out completely random. I've been able to see codes 14 and 34, which both are related I believe. (34=Ignition proving failure; and 14=ignition lockout. Until today I've never been able to see first hand what was causing it to go into the error mode. It works more times than it doesn't, but it has been daily. If it goes down and you turn the power off/on it will go right back to work, but at some point later it will be out. I've gone so far to cycle the furnace 8 times every 5 min and it worked every time. So today I go to set up a camera and while I'm by the furnace a "call for heat" comes and I watch the furnace go through its cycles. Well after the HSI was glowing and the gas valve opened up, it failed to light. On the re-try it did light. I'm left to assume that at some point, it is doing this same thing, only failing 3 times in a row and going into lockout for 3 hours. Scott

I bought a HoneywellRTH6500W Thermostat. It requires a C wire that I don't have. I have a free wire that goes to the Furnace. Can you help me to find a C stationary on my Furnace: Trane XL 80 with a White Rodgers model 50a51 495 Does it has a COMMON stationary 24VAC? Can I use the Comm stationary? Picture attached. (but I measure ~50VAC instead of 24 VA) Thanks for your help Serge