Hi there,

I live in Seattle. We have a tempstar furnace model # nuge075ag02. The problem is that the furnace does not stay on. It starts up fine, runs for about a minute, shuts off, restarts again for a few seconds, shuts off, starts again, shuts off. I'm wondering what I should check. I've isolated the thermostat and that doesn't seem to be the problem. I've read posts that say to check the flame sensor. I rubbed the face of the sensor with some sandpaper. No luck. Hoping some one out there can shoot me some suggestions. Thanks for the replies.

Soundls like a drain problem and the vent motor is getting water in it causing it to kick out on pressure switch.

Or maybe something blocking the flue,, check it all the way, even inside the inducer housing

Check status LED, if present.