My home has coleman evcon furnace 12 years old.I can set the thermostat at 74 degrees and the furnace will start with a 30second purge then the ignitor will warm up and glow red then the main burner lights.then the burner stays lit and the blower runs for a couple minutes. Then the thermostat calls for heat the igniter will glow red again but the burner does not lite and the purge fan will come back on and continue to run.then I have to shut the thermostat off and turn it back on and the furnace will cycle and run another heat cycle or two and then it will not ignite the main burner on the next call for heat.the furnace will only go threw the ignitor glowing red then to purge.the hot surface ignition module was replaced 2 years ago.what do you think the problem is?:confused:

Look for a diagnostic light next time it locks out. See here.

We have had the same problem with our Coleman Evcon furnace. The indicator light was blinking 3 times. We originally replaced the Limit switch which did not help and then we purchased the whole blower assemble for about $200.00 dollars and that didn't take care of the problem. At first after testing we thought we got a bad blower assemble and then my husband said less try one other thing. We replaced the thermostat. The original one seemed like it was working fine but lo and behold when we replace it the furnace started working fine. TRY THIS FIRST to save yourself some money. We even thought it might be the circuit board. We tested the blower with a multimeter and the readings on it showed the new blower assembly was bad. I contacted the company we purchased it from and they said we would have to purchase another one and they would have to send the supposedly bad one back to coleman and if coleman found that it was NOT bad then we would own two of them. At $200.00 a crack we decided to try to analyze it again ourselves. I hope the replacement of the thermostat works for you as it did us. Try it, hopefully this will solve your problem at a less of an expense.
At least we are not freezing anymore.

We are having the same problem. I installed a new thermostat. Sadly our heater is not kicking on. L cleaned the ignition assembly and sensor with emery cloth. I reinstalled and tried again the main burner does not kick on. I noticed the yellow light came on along with a green. Does anybody know what that meana ?

We are having the same problem. I installed a new thermostat. Sadly our heater is not kicking on. L cleaned the ignition assembly and sensor with emery cloth. I reinstalled and tried again the main burner does not kick on. I noticed the yellow light came on along with a green. Does anybody know what that meana ?

What does a yellow light on the indicator mean?)