Carrier RAV Intermittent Problem (Help!)
bigMikeB...my apologies. I don't think I was clear. Sometimes the igniter would turn on and then off but also sometimes the burners would in fact turn on and they too would just shut off. The igniter always got hot though. Now this was when it was not working. There were periods when it would work for a few hours or even days and then stop. You're right about the guy though. Nice guy but I can't comment as to the comparison of the timing of the two boards. It's not like I'm so in tune with them that I could tell. He also, I think, tried to use some scare tactics telling us that the ducting was very poor and there were stress fractures on the fire box (heat inducer) and that it was his "job" to tell us especially since we have a 2 year old. I'm not really sure what he was talking about. Maybe I'll install some carbon monoxide detectors in the house...probably a good idea anyway. The thing is my parents furnace in the house I grew up in was the original from 1920 and lasted until 1990. I have a hard time believing that my 12 year old furnace is at the end of it's life. Anyway, his diagnosis of the problem seems to be working so far. In fact before I went out today and bought one I was able to replicate what he told me. I put my meter on the valve and kept turning the system on and off until it failed. When it was failing the thermostat would call for heat and the cycle would start. You would hear the valve click and I would see voltage on it but then no gas (or there was gas for a short time and then the valve would close) even though there was still 24 volts on the valve until the flame sensor signaled the board to cut power to the valve. I replaced the valve today and so far so good. I did buy the flame sensor since it was only $20 and I'll just keep it around just in case. So the board was $90, the valve was $80 the flame sensor was $20 and the diagnosis was $80 so all in all I spent $270 which is still less than half the $550 they were going to charge me to change the valve only. I'm sure changing the board would have been another five or six hundred dollars.
Now that I think of it he said one more thing which I don't know if he was trying to blow more smoke up my ass. He said that a proper installation of the ducting doesn't even use dampers at all for balancing the system. That if he did the installation he wouldn't even need them. I find that hard to believe in normal size house. How would you balance the system otherwise. Different size ducts for rooms that are at different distances? Anyway, thanks for the help. Two weeks ago I knew completely nothing about furnaces so at the very least my money was well spent on my learning this.
Last edited by ezmamos; 01-12-2008 at 02:28 AM.