My drolet eco-45 doesn't want to start up. A little history; I noticed this started awhile ago in increments. I have no thermostat and use manual start up. I pressed the button to manual setting and there was a slight hesitation before complete startup. Worked as it should. After a week, shut in down to clean, no problems. Re-started, and noticed a little longer hesitation. This went til it finally it wouldn't start at all. I removed both tubeaxial blowers (convection blowers) and cleaned thourghly. The original installer did not put filters in place. Opened back and cleaned the combex blower as best as I could do without removing it. I tested the auger feed and it works. Just a note, when I start it up, I hear a slight humming noise, like from a stuck electric motor, even with both tubeaxial motors removed. I'm thinking the combex electric motor is malfunctioning but would it humm if the pressure switch is defective. Any thoughts. Thanks