Mt Vernon Won't Ignite - Mistake in installing Ignitor

JK302 said:

.... the cleaning action cut the wire and shorted it out. .......What should I check next?......

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fuse(s)? Is there any voltage going to the ignitor wire at all during start-up?

imacman is right, if you cut the wire with the autoclean and shorted it out, you also probably blew the ignitor fuse. Cheap fix.

JK302:

I don't know the Mount Vernon stoves in detail but I believe most of the controls on these pellet stoves are very similar.

If the ignitor wires were pinched enough to blow the fuse, this may have also damaged the ignitor control circuit back in the controller box. In my Whitfield, the ignitor is controlled by a medium (~10 amp) current relay. The relay coverts a low current low voltage control signal to a 120VAC 3.33 amp power signal to drive the ignitor. The fuse is in the ignitor circuit to protect the relay's output contacts and avoid a fire situation. The good news is the fuse has obviously avoided the fire -- but the bad news - the fuse may not have fully protected the relay output cotacts. This is not uncommon on a partial or intermittent short situation. Fuses are great at responding to 'dead shorts' but can be 'slow to blow' or inadequate with a partial or intermittent short. You had an intermittent short issue. That's why your stove ignited sometimes - and sometimes not!

If you are familiar / comfortable with the operation of a volt meter, you need to check the voltage drop across the ignitor when the stove is in ignition mode. It should be at line voltage (117 +/- 3 VAC). If it is anything less than 114 VAC then the relay's output contact resistance has increased (partially burned) and is limiting the power to the ignitor. A voltage of 30, 40 70, 100 VAC would clearly indicate this.

If the voltage is zero VAC the fuse may have blown again or there is an electrical contact problem (open circuit) some place in the wiring harness.

You might also check the resistance of the ignitor with the pinched wires. If this is a 400 watt ignitor (typical for a pellet stove) the resistance should be 38 to 40 ohms. If you find this resistance, the ignitor is OK - you only need to repair the power leads and you will have a spare ignitor! Don't toss it, they're expensive.

Good luck. Let us know what you find.

RonB