Mt Vernon AE Vacuum Issue

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Peter Martin

Member
Oct 27, 2013
37
Chappaqua, NY
I have a question which highlights the fact that I don't understand the physics of my stove. I'm getting the vacuum switch error. When I bypass the vacuum switch, the stove still does not light, but pellets drop. About 5 minutes after the pellets drop, I'm getting some smoke around where the stove interfaces with the aluminum pipe vent to outside. So, there's definitely an issue there. My question is, why is this a vacuum issue? I would have thought that there is only a vacuum in the firebox and after the exhaust blower a leak wouldn't cause the stove to not light. After all, the other end of the vent is the top of my chimney, so it's open air.

Also, I'm having trouble plugging the aforementioned leak at the stove to vent interface. Does that little cloth gasket wear down over time? Could it be that that gasket is done, which is what is causing the leak?

Thanks,
 
Have you pulled off the vacuum tube and blown it out?I would try that
 
I'm pretty sure it's not the vacuum switch. When I bypass it, pellets drop, the igniter fires up and tries to heat the pellets, but the pellets just smoke and never catch fire. That suggests to me that I don't have a vacuum in the firebox. I replaced the rope gasket on both the ashpan and the door yesterday, but that didn't help. What else can I look at?

Thanks,
 
Sounds like your vent is clogged. When is the last time you had your stove and venting cleaned? The vacuum switch is there as a safety mechanism so that if you have a blockage in the pipe (or the ash traps in the stove) it will not allow it to feed pellets so you don't smoke yourself out. It can also be tripped if the ash pan is out or the gasket is bad but that's a MUCH less likely scenario here. Of course the pellets would feed if you jump the vacuum switch... your bypassing the mechanism completely. But the fact that the pellets wont light when you have it jumped tells me you have a blockage somewhere. I'm like 90% sure that's your issue. Pellets need good airflow to burn, if they aren't lighting and the combustion motor is running its because the air has no where to go so the pellets would just smolder.
 
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Yeah, you're right, it's got to be the chimney. I have a long run to the chimney and I must not have gotten it all clear when I did it myself. Time for a chimney sweep.

Thanks for the help.
 
The fan on the right is easy enough to get off and lay up on top of the housing ( dont have to unplug any wires). then take a brush right thru the fan housing and up to the top of your chimney. As long as you dont have hard pipe 90's. Or you may find it is plugged up right after your fan housing and run a shop vac hose up there and get it.
 
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