(this unit was with the house when my son bought it and heat is only problem at this time, cannot afford new unit)
Make : Lennox
Model : G40uh-36a-070-03 no diagnostic lights flashing
new prove switch acting same as old switch
Had this problem last winter and A/C tech put in new prove switch and it worked till it quit a few days ago.
when the t-stat is calling for heat, the air inducer starts and runs and after a few minutes the unit still does not ignite. Then i play with the prove switch and pull a manual vacuum and unplug and replug the prove switch wires and it will finally start the ignitor and fire up, it may run for days or till heat cycle ends.
When the combustion air inducer starts running, is it suppose to create a vacuum to hold the prove switch open or closed so the furnace will ignite ? While it is running, I placed a dime sized piece of saran wrap over the pressure port and it would not stay, that tells me the air inducer is not creating vacuum to hold switch o/c. Can this fan be removed and be cleaned so it will pull vacuum. or am i missing something... help please
Make : Lennox
Model : G40uh-36a-070-03 no diagnostic lights flashing
new prove switch acting same as old switch
Had this problem last winter and A/C tech put in new prove switch and it worked till it quit a few days ago.
when the t-stat is calling for heat, the air inducer starts and runs and after a few minutes the unit still does not ignite. Then i play with the prove switch and pull a manual vacuum and unplug and replug the prove switch wires and it will finally start the ignitor and fire up, it may run for days or till heat cycle ends.
When the combustion air inducer starts running, is it suppose to create a vacuum to hold the prove switch open or closed so the furnace will ignite ? While it is running, I placed a dime sized piece of saran wrap over the pressure port and it would not stay, that tells me the air inducer is not creating vacuum to hold switch o/c. Can this fan be removed and be cleaned so it will pull vacuum. or am i missing something... help please