Furnace Unit: American Standard downflow gas fired (natural gas) "fan assisted combustion system" (model cdb080a945co)
Installed in 2000
History: When this house was being built in 2000, there was significant conflict between the local HVAC installer and the out of area building contractor. Every time I seek service or maintenance from the installer, he rags on the contractor and offers far less than satisfactory service (requiring repeat visits for the same problem). Now I'm facing a potentially broken furnace and I don't trust his diagnostics or to fix it right. He says it will cost(((( $X amount of dollars)))) to just come out and look at it.
Past Problem: 1. Thermostat calls for heat. (Integrated furnace control red led light flashes fast (normal operation so far).)
2. Control module verifies pressure switch contacts are open and limit switches are closed and the draft blower is energized. (Red led continues to flash fast.)
3. Pressure switch contact close and ignitor warms up (I have visual confirmation that the ignitor is warming up.)
4. The gas valve is supposed to be energized at this point. Instead, it shuts down (with a "click"), waits for a few seconds, and begins at step 1 again. (Red led continues to flash fast.)
Current Problem: 1. Thermostat calls for heat. Process begins with normal clicks, etc. but then the red led indicates (with three flashes) a Pressure Switch Error. I've been trying to work with my HVAC installer to understand the situation before calling him out to fix it. He initially claimed that the board or ignitor needed replacing and then said the pressure switch needed replacing. I checked his story against posts on the internet and have not been able to get a clear verification of his story. I'm just not willing to have him come out, as he's done in the past, and charge me several times without fixing the problem.
(No pricing please) please read http://hvac-talk.com/vbb/showthread.php?threadid=1241
[Edited by fixit50 on 03-26-2005 at 09:03 PM]