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?