MMHB-07ABHR-06 intermitent problems

[deere97]

This furnace will run for several weeks then lock out and give the 3 flash code. I power off and reset and it works fine for several more weeks. Today I have noticed it will call for heat and the burner fires. It stays on about a minute and goes out and then 10 or so seconds later will fire up again. The blower does not operate till after the second series of burner. Is this normal or am I starting to have issues. It is a 1996 furnace. 1 draft motor and 2 igniters is all the trouble in 12yrs.

[Robert]

Hi,

Three flashes is a failed ignition attempt, gas valve error or false flame sensed during warm up period.

You should never reset and continue using without finding reason for lock out and resolving that issue.


It would be best to have an hvac tech come and diagnose which problem is causing this and repairing correctly.


Thanks,
Robert