[schlitz]

My miller home furance MMHA-077ABHR-02 has a UT Electronic Controls 1018 series hot surface ignitor that flashing 3 times. Furance goes through the cycle for starting, solonoid for gas opens momentarily and shuts right back off, and furance will not stay burning.

[lilpoppa]

Sounds like you have a bad thermal sensor, your furnace will go through the start up sequence but will not stay lit because it is not reciving a signal from the thermal sensor, the system thinks that the burner has not ignited and closes the gas valve to prevent a dangerous gas leak. Check the electronic connections for corsion or damage. If that doesn't fix the problem you may need a service call from a professional who can preform diagnostics on the electronic componets of your system.

[T-Top]

If the ignitor glows and the burner lights and then goes back off after about 3sec. I would say you have a dirty flame sensor. It's a small metal rod that sets in front of the burner, one wire will be going to it. Scrape it clean with a knife. (DO NOT TOUCH OR CLEAN HOT SURFACE IGNITOR ITS VERY FRAGILE).

[DuRagg]

If you haven't fixed it already, it could be reversed polarity. This happens a lot. People plug in their pigtail upside down if no ground. By the way don't clean your flame sensor with a knife they are very delicate and work off milliamps. The only way to correctly clean a flame sensor is with a dollar bill. It will not damage the part or ruin it with fuzz.

[bigdaddy31674]

I have a similar furnace in my home and experienced the same problem. There are three elements of fire; Fuel, air, and spark. If the flame is igniting, its getting spark(or glow plug style ignitor). If the flame doesn't last or gets weak it is losing air or fuel. Most likely, with your model , it's not losing fuel, it's probably not getting enough air. Remove the inducer motor, 5 bolts including the ground wire. You'll want to remove the ground wire and disconnect motor so you can completely remove motor and squirrel cage. Check for debris in the squirrel cage or obstruction in the duct above the motor. When I removed the motor and squirrel cage on my furnace I found a dead bird wedged in the duct just above the motor restricting air flow. Works like new now.