I have a York Diamond 90 Furnace and the burner would stop after few minutes with LED blinking 6 times. If I turn off the heater and turn it ON again the burner will start but will shut off after few minutes and the blower keeps blowing cold air. Can anyone suggest what can I check.
6flashes means it's time to replace the furnace! Just kidding!
Actually, if you look on the inside of your furnace panel you should see a diagnostic chart that will translate the code. Then post again telling us what the code means.