Harman p68 ash burn pot

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Nov 15, 2014
Val-d'Or Québec
Hi all Happy Holidays
I have a harman p68 I want to know to have the maximum efficiency of the stove is it better to keep the ash accumulated on the edge of the burn pot or to remove it completely because when it is not very cold the stove works almost at the minimum to keep the temperature in the room and maintaining it, however the ashes accumulate on the edge of the burn pot but if it is colder the stove works harder and the ashes do not accumulate.
The stove settings are
feed rate 3
room temperature
The accumulation of ash has nothing to do with the efficiency. As long as the ash accumulates about an inch at the edge & gets pushed out of the burn pot into the ash pan , everything should be good. Stay warm & enjoy!
Thank you
I was wondering since the flame rises less high when there is ash that the heat was more sucked up by the combustion motor and came out through the chimney and heated the heat exchanger less
When there is no ash the flame goes straight up to the heat exchanger and with ash the flame is bent and goes out to the door glass
One inch of ash. That's about it. I quickly pull mine off once a day if I'm doing 24 hour burn, also depends on quality of pellets..
"maximum efficiency" is irrelevant, as the stoves are also programmed to meet emissions spec's. As far as heat going up the chimney, that is part of life of any heating device that burns a solid or gas fuel. Also remember, the pellet feed also changes the speed of the combustion fan, to balance things out, for less waste. If you strive for "maximum" heat from a pellet stove, in all conditions, you will end up with not "enough" combustion air, and a stove that gets very dirty, very fast. Anyway, the "ash line" only relates to the stove burning on high, and after a period of time. In lower settings, or, stove ramping up or down, it means nothing, the whole pot can almost be full of ash, but will be pushed out as stove ramps up speed of the auger. That is why the feed setting is called a "max" setting. Maybe newer manuals don't explain as well, will post something from older Harman manual--

"Setting the feed adjuster # for maximum burn: With the unit
burning in "AUTO", turn to "Stove Mode" and put the fan on "H".
Set the Temperature Dial to #7. Allow the unit to burn for about
30 minutes and check ash on front of burn pot. Fig. 9. If the ash
line is larger than 1", turn the feed adjuster from #4 to #5. Allow
another 30 minutes of burn time and check again. If , at #6
setting, a 1" or less ash bed is not obtainable, it is not a
problem. The 1" ash bed is only a maximum burn rate and at
most normal settings the ash bed will be larger."
Thank you for your answers
Have you tried room temp manual? I like that way better than auto.

When I fire the stove up, I push the bigger fluffy ash into the ash pan, and scrape the bottom and sides of the burn pot down into the burnpot. The pellets will push it back out and some of it will burn again.