How do You adjust the minimum feed rate p38+

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C4boom

New Member
Dec 8, 2019
13
New Hampshire
I just upgraded my stove from the old 2 knob to the new 3 knob control board. The idle feed rate seems to be a little high. Stove is heating my living Room up without even demand from the thermostat thermostat set at 65゚ Room was 70゚
 
I just upgraded my stove from the old 2 knob to the new 3 knob control board. The idle feed rate seems to be a little high. Stove is heating my living Room up without even demand from the thermostat thermostat set at 65゚ Room was 70゚

Set the thermostat at 60*F;) Depending on where your temperature sensing wire is located and its specific characteristics you may need to use a setting a good bit lower on the dial than the indicated temperature. I my own situation I need to use a setting of ~ 57*F to arrive at a room temperature of 65*F. Hope that helps.

Hugh
I just upgraded my stove from the old 2 knob to the new 3 knob control board. The idle feed rate seems to be a little high. Stove is heating my living Room up without even demand from the thermostat thermostat set at 65゚ Room was 70゚


Have you tried setting the thermostat lower? In my situation I need to set the thermostat on at ~ 57*F to have the room maintain 65*F. Without an igniter you'll be hamstrung in situations where the need for heat is really low.
 
Befor I left today I installed a normal house thermostat that way it makes the stove go into a status 4 code. It currently is 43° outside. The inside thermostat is set to 60° and the room is 71°. I just checked the total run time for heat demanded on the thermostat and it is currently at 0 for the day.
 
Befor I left today I installed a normal house thermostat that way it makes the stove go into a status 4 code. It currently is 43° outside. The inside thermostat is set to 60° and the room is 71°. I just checked the total run time for heat demanded on the thermostat and it is currently at 0 for the day.

If I remember correctly the absolute minimum feed is ~ .7lb/hour on the P38, P43 and Accentra stoves. At that rate one would expect ~ 4,500 btus per hour output from the stove. In the case of the house where I live, that would keep the house in the mid to high 70s when it's in the mid-40s outside. Luckily for me with a P-43, the stove just shuts itself down and doesn't re-light itself until it cools to the set temperature. So for example, last night when it was in the mid 40s outside when I set the stove to maintain ~ 60*F at bed time, it shut itself down for the whole night and only relighted after I got up at 7:30 and set the temperature back up to 68*F. Auto-light is a wonderful feature during the shoulder heating season! I don't believe you can set your P38 up for a lower minimum maintenance burn.
 
You would have to basically convert it to a P43. Replacing burnpot, circuit board and wiring harness and circuit board mounting plate. I may be forgetting some smaller items
 

Here is the link to the discussion of when I converted mine.
 
Ok. I tried to run my 38 as low as i could and ended up building creosote in the flue and had a minor chimney fire. That is why I ended up converting to auto ignition so it would burn hot then idle down for a while then go out. Then refire as needed. You need quite a bit of heat demand to keep from over heating the area. And the Harmans are not very handy to hand ignite. My St Croix is not auto ignition but it is a breeze to light. Pour a cup of pellets in, a squirt of gel, throw a match in and start stove and leave for work. Lights that easy every time. I never figured out how to light a Harman by hand that easy in the 16yrs that I have had it.


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Ok. I tried to run my 38 as low as i could and ended up building creosote in the flue and had a minor chimney fire. That is why I ended up converting to auto ignition so it would burn hot then idle down for a while then go out. Then refire as needed. You need quite a bit of heat demand to keep from over heating the area. And the Harmans are not very handy to hand ignite. My St Croix is not auto ignition but it is a breeze to light. Pour a cup of pellets in, a squirt of gel, throw a match in and start stove and leave for work. Lights that easy every time. I never figured out how to light a Harman by hand that easy in the 16yrs that I have had it.


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I had my own creosote/chimney fire excitement early on with my P43. It occurred during my first shoulder season when the stove was overheating the cabin even on the lowest manual setting. In a misguided attempt to conserve the igniter and pellets I ran the stove in manual stove mode with the feed set down just above Test. When you run that way, the distribution blower runs continuously and the smallest of fires is maintained. In hindsight that's the surest recipe for creosote formation. I also wasn't vigilant regarding running a good hot fire regularly to burn off a slight accumulation. So one day when I did run a good hot fire after a couple of weeks of very low burn things suddenly smelled hot. The rather eery red glow coming from the stove pipe clued me as to what was going on. The event did cause an ESP error code but thankfully that went away after things cooled down and I pulled and reapplied power. Lesson learned.....if you run the stove too cool you'll accumulate creosote.

Hugh
 
I know this sounds nuts but I have been using alchohol based lighter fluid in my stove for years. Just dont go nuts with it just a squirt. My start procedure is chuck a hand full of pellets in the pot turn the stove on ,give it a squirt and light. Takes less than a min and it starts every time.

As for creosote I have a wood stove that runs 24/7 from November to March so i sweep my chimney every year and my flue pipes. On the pellet stove side there is almost never anything. I did set my stove up with a manometer and adjusted the high low draft. The flame is always bright and snappy even on lower settings.
 
I know this sounds nuts but I have been using alchohol based lighter fluid in my stove for years. Just dont go nuts with it just a squirt. My start procedure is chuck a hand full of pellets in the pot turn the stove on ,give it a squirt and light. Takes less than a min and it starts every time.
That is great. I had always struggled lighting mine with gel. It burns great once it got running but I dreaded lighting it. And I have been a Harman Tech for 15 yrs!

As for creosote I have a wood stove that runs 24/7 from November to March so i sweep my chimney every year and my flue pipes. On the pellet stove side there is almost never anything. I did set my stove up with a manometer and adjusted the high low draft. The flame is always bright and snappy even on lower settings.
The ceosote was my fault for leaving it run just as low as I could get it to go. I would turn down until it was off then bump til it would just come on. Just so I would not have to relight the next day. My stove is in the basement so I have about 2' Horizontal run then 7' vert run then 3' horizontal run. almost all 4". So flue gases have time to cool to the point of creosote formation if run to low.
 
My stove is run with 4 inch for 3 feet a 90 then 6 inches into a brick and clay chimney. Also all my 4 inch pipe is triple walled.


The ceosote was my fault for leaving it run just as low as I could get it to go. I would turn down until it was off then bump til it would just come on. Just so I would not have to relight the next day. My stove is in the basement so I have about 2' Horizontal run then 7' vert run then 3' horizontal run. almost all 4". So flue gases have time to cool to the point of creosote formation if run to low.