I HATE my FU*KING FURNACE!I have a York Diamond 90 furnace that wont heat above 65 deg.This is not the first time this has happened, but historically all Ive had to do was clean the vent lines. Well that has been done, and Im still having the same issue.It fires up and runs fine, but then the flames begine to sputter (after about 5 mins), then the go out. I get 3 blinks on the indicator signaling a sticking pressure switch. The unit eventually turns completely OFF, failing to reach temp.Anyone know about these machines that can lend some info!?Im LAME on this topic!Please HELP!Chicago