I have a Goodman GMP100-4.

It does not ignite. I have followed the written instructions and cleaned any debris arount the unit. Suggestions?

Does it have a spark-box? Does the fan come on?

XenoSapien

It has a box. The fan does come on, then the light on the board flashes three times and the fan shuts off.

Go to https://www.askmehelpdesk.com/heatin...ons-58313.html

Do you have a decal that lists 3 flashes, or flash, pause, flash, flash (12) as pressure switch open? Check and clean the hose from the pressure switch. Suck on it and see if the switch clicks.