I have a Goodman Furnace Model GMT045-3A that stopped working from one day to the next. I noticed that the blower kicks in but the igniter will not turn on. The board has a red light that after a few seconds starts blinking three times. It continues to blink 3 times, stay off for about two seconds and blinks 3 times again. This pattern will continue until I turn off the furnace. Any ideas how I can find out what the three blinking lights mean or get the igniter working again.
Pressure switch was not closing. I blew air in and out of the rubber hose connected to the switch until I could hear and feel it closing and opening. After connecting it back to the fan inlet the furnace turned on and it is working again.