I'm at my wits end with my furnace. I have a 2003 Gulf Stream Conquest TT with a Suburban SF 25 furnace. Nothing happens when I turn the thermostat on. I checked the continuity from the thermostat. I have power to the ignitor board. I have checked the sail switch, limit switch and both work as they should - I put heat to the limit switch to verify that it works. I put power to the blower directly and it runs fine. I thought that maybe the ignitor board was bad, so I replaced it with a Dinosaur 50 plus pins, but still nothing. Is there something that would stop the blower from working? Can I assume that if the ignitor or gas valve were bad that the blower should still come on?
SEQUENCE OF NORMAL OPERATION
1. When the thermostat calls for heat, the blower motor is energized immediately.
2. As the blower motor reaches approximately 75 percent of the normal rpm
(within 3 to 5 seconds) the microswitch, in response to the air flow, will engage
allowing current flow to the solenoid valve and the spark ignition system.
3. The current to the valve opens it and allows gas to the main burner. The spark
then ignites the main burner.
4. After main burner ignition, the flame detector will sense the presence of flame
(usually within 7 seconds) and deenergize the lockout feature. If the main
burner does not ignite or the flame detector does not deenergize the lockout
feature within 7 seconds, the unit will go into lockout. At this time, it will be
necessary to set the thermostat on OFF and repeat steps 1 through 6 of the
5. After three (3) attempts with no ignition or main burner continues to go off
within 7 seconds, go to shutdown and determine cause. (see service hints)
6. If within a period of approximately 2 minutes after the main burner is lit, the
thermostat is turned back, both the blower motor and solenoid valve are
deenergized. However, if the furnace continues to run longer than 2 minutes,
which it normally should, a slight snap can be heard from within the casing. The
snap is caused by the fan switch as it changes its position. After this occurs, if
the thermostat is satisfied or turned back, the solenoid valve will close, the flame
o n the main burner will go out, but the blower will continue to run for a short
period of time and will then shut off. The purpose of this is to remove most of
the remaining gases from the heat exchanger. Be assured that this period of
blower override is a part of the unit’s normal operation.
2005 Southwind 32vs F53 Retired
2006 Jeep Liberty 4x4
Blue ox Tow Bar
OK I feel like a boob! I knew it would be something simple and stupid. The white connector that attaches to the board with 4 wires had a loose connection for the ground (yellow wire). It was pulled out just enough that it wasn't making a connection. I pushed the wire all the way in and re-connected it to the board, then it came out again. I ended up re-routing the wire so that it had a little more slack.
The funny thing is that we don't really use the furnace, as we have a ceramic heater that does a great job, but it was driving me nuts that the furnace wasn't working. It's just the way I am "wired".
Thank you to those of you that replied. One more item checked off of the "to do list".
Hope to make it to Fort Custer this coming weekend!
I do not believe a 2003 would have had a fan control board from the factory, it would have had a standard time delay relay. On these models there is a 30-45 second delay before anything happens.
With the Fan50, does the green LED light up?