Fine tuning a PF100

[fiddlesticks]

I am up and running with a Harmon PF100 and have two questions. 1st...my home is about 2500-3000 square feet and I am burning about 4 bags per day to keep it at 68 degrees. I upgraded to the 1500 FPM fan per the advise of the dealer and am on the outer limits per spec for horizontal (14.5 feet) for vent. It seems this is a lot of pellets. Any thoughts on if this seems OK or if there is something I can try to reduce the burn amount? 2nd...some smoke comes out the vent when the furnace is burning on high. M neighbor has a P57 with a vertical only vent and doesn't get any visible smoke. Is some smoke OK?

Thanks

 

[exoilburner]

I have been running a PF100 pellet furnace for about 10 months. I have a similar square footage house (and poor insulation) and am close to the outer limits of vent length. During the coldest weather I burn around 2 bags of pellets a day max. Coldest nights around here lately have been in the 30s. I turn the thermostat down to 60 overnight 70 actual degrees all day. After starting it up I switch the AUTO/MANUAL-LIGHT switch to MANUAL; this keeps the PF100 in a low burn rather than go out and reignite all night. So it runs 24, 7.

I noticed that my PF100 smoked out the vent for a couple of months after I started using it. Was a little worried about that, but now it is smoke free after the normal startup smoke. The operating manual says if smoke is coming out of the vent (see below) that is a problem. If you are getting excessive smoke and high pellet usage possibly it is feeding too much fuel causing the combustion fuel/air mix to be rich. Feeding more pellets than the combustion can handle.
The operators manual pg34 says:
SMOKE IS VISIBLE COMING OUT OF VENT
1. Air-fuel ratio is too rich.
A. Feed rate too high.
B. Draft too low caused by a gasket leak.

The Harmon operating manual says the best setting for the pellet FEED ADJUSTER is 4. Sometimes mine smoked on low burn so I turned the FEED ADJUSTER down to 3.5 and it seems to have solved the low burn smoke.

Also there are DIP switches on the CONTROL BOARD that set the pellet feed rate. If your PF100 is still under warranty tell the dealer about the problems and have them check the switches. Do a search for DIP switch on this forum to get more information.

Another thing to check I have seen on the forum is to check the PF100 backdraft damper to see if it is swinging freely. They have been known to stick and restrict combustion air draft. Some of the posts on the forum say a small drop of light oil on the backdraft damper pivot points fix the problem. The damper is located under the pellet hopper on the right side. Behind the lower cover.