Furnace control board problem....*

[runman49]

I have a York gas furnace (- P2MPD11408435) with a control board (Part#031-01234-000 Johnson Control). By turning the power on and off, the furnace works fine with the first cycle.....and after the desired temp is reached, the furnace turns off as it should. However, when the low temp on the thermostat control is reached, instead of the next cycle repeating, nothing happens and the Control Board LED has a single flash every 3 secs...The LED code says this means “Lockout – Check furnace”. If I turn the power off and wait about 20-30 minutes, the LED no longer blinks and I can then get the furnace to work again but for only one cycle again. I have replaced the Pressure limit switch, placed new filters and ensured that the inducer motor exhaust pipe is clean and unobstructed. I am now thinking about replacing the control board. any other thoughts/*

thx

[runman49]

thx for the reply. With respect to "nothing happens" I am fairly certain that the furnace will not attempt to fire (inducer,ignitor,gasvalve) but instead goes right into lockout. Also, I believe that the switch I replaced was the pressure switch (but not sure) --> it had a 10" long plastic tube that was connected to the inducer motor...I replaced it because it was easy to do. I am unsure what the limit switch does -- is it the temp limit * I did also replace another switch that was a small unit about the diameter of a quarter (and about 1" tall) that had a flat bottom surface that was attached to the gas manifold assembly.

thx

[runman49]

Replaced Control Board...furnace works great

[juster]

Thanks for the feedback