Harman Advanced FS burning issue?

[Don2222]

Hello

My friend has a Harman Advance FS pellet stove in front of her fireplace. The vent is connected to a Cleanout T and then it goes up a 25 foot chimney. There is no OAK. The problem is the lit pellets go out in the middle of the burn pot but stay lit on each side. Then the middle piles up with unburned pellets. This happens more with Home Depot FireSide Ultra wood pellets than the NEWP brand. Higher ash content does not help.

I thought Harmans could burn anything?
Is there something here that could be done to make the higher ash pellets work alot better besides using a higher heat setting?

 

[jtakeman]

Don't you mean customer?

Play with the feed rate. If its pushing unburnt into the ash pan the feed rate is a tic to high.

 

[Don2222]

Don't you mean customer?

Play with the feed rate. If its pushing unburnt into the ash pan the feed rate is a tic to high.

My friend works as a cashier at Home Depot so I see her all the time! LOL

However, can the feed rate be higher and maybe up the burn air too?

Not sure about Harmans. I really want one to rebuild but everytime I see one cheap it is gone before I email them!

 

[jtakeman]

My friend works as a cashier at Home Depot so I see her all the time! LOL

However, can the feed rate be higher and maybe up the burn air too?

Not sure about Harmans. I really want one to rebuild but everytime I see one cheap it is gone before I email them!

Check the feed rate. It should be close to 3.5ish. The burn air is computer controller AFAIK. I think the only thing you can play with is feed rate dial. Its been a while. Where's the Harmone peeps at today?

 

[TheMightyMoe]

Plug in your Harman Diagnostic tool, and see what it says.

 

[New Hampshire Jim]

Excerpt from the Sticky at the top of this page (How Harman Stoves Work))Feed Rates - Feed rate is controlled by the stove ESP. The stove will select a feed rate based on the actual temperature and target call for heat. The larger the temperature delta (actual room temp vs. target room temp), the greater the feed rate will be. 10 degrees would be a large delta and the stove would feed to reach max ESP temp of about 500 degrees depending on stove model. A 2 degree delta might only result in a feed rate of 20 seconds per minute even though the feed rate max dial is set to 4 (or 40 seconds per minute). The stove can vary the feed rate between 2.5 seconds per minute and the max feed rate you set. A feed rate of 6 would represent continuous feeding if the ESP wasn't seeing sufficient temperatures to satisfy the call for heat.When up to temp the stove will regulate itself form 2.5 seconds per minute of feed up to the limit you set.

Feed rates can lead to incomplete combustion comes in 2 forms:

1. Pellets spilling over the edge of the burn pot before they are reduced to ash.
2. Smoke.

Relative to #1 - when you run the stove wide open (stove temp setting at 7), the burning pellets should come no closer than 1 inch from the edge of the burn pot. You should have burning pellets and about 1" of ash before the edge. If pellets are bulging and close to the edge, you might not turn them to ash before spilling over the edge, wasting energy. If the burn line is too close, dial the feed rate back a bit, may by 1/2 of a number (i.e. 3.5 to 3). The stove doesn't run wide open once everything is up to temp, so this is only for scenarios where, for instance, the room is 65 and you want it 75 degrees or you turn the temp dial all the way clockwise (just don't walk away for too long or you'll bake yourself...).

Relative to #2 - smoke is also a sign of incomplete combustion, meaning that there is more fuel than air supplied by the combustion blower. This too should be evaluated when the stove is running WIDE OPEN. At night with a flashlight, you'll always see smoke. During the day, smoke is rated based on opacity or how easily you can see through it. Startup might be 50% opacity or fairly heavy smoke. If you are 10% or less (barely visible), that's reasonable and you aren't really wasting anything. If you have to struggle to see it, you're probably good. If you can easily see smoke and your flame is HUGE, try dialing back feed rate a bit to bring the air/fuel mix back into a more efficient range by dialing it back by 1/2 of a number (ie 3.5 to 3). In most cases, you don't want to be below 3 or much above 4. You'll also want to recalibrate after changing brands of pellets since the blend and size of pellet will cause it to burn/feed differently.

Setting your feed rate too low doesn't save pellets and stove performance will suffer since your inhibiting the ESP from reaching target temps. Setting your feed rate too low is like putting a brick underneath the gas pedal of your car.
Jim

 

[Harman Lover 007]

Check the feed rate. It should be close to 3.5ish. The burn air is computer controller AFAIK. I think the only thing you can play with is feed rate dial. Its been a while. Where's the Harmone peeps at today?

Sounds like the burn pot holes may be clogged or there is a large buildup of ash in the burn pot ash compartment. Remove the two small wing nuts and open the little door. A crevice tool on the vac works great. Take a paper clip and make sure all the holes in the burn pot aren't clogged.

 

[mepellet]

I also vote for holes in the center clogged. The speed bump seems to be larger in the middle in my stove.

 

[P38X2]

X3. Seems logical. Sounds like it needs a good cleaning.