Harman ESP question

[P43pig]

Ive been running a p43 for 3 years now and it have been great, awesome stove. Reason I bought it was because I built a house and was having trouble bringing the gas line in, so rather than giving money to the propane company I put it into a stove. The stove did its job and pretty much paid for itself in one season. But now that the gas line is in it has taken a back seat in heating the whole house...I still want to keep the stove but I'm trying to tune it where it's most efficient.
Here's what I have...I built a sunroom (16x16) off the back of the house that connects to the house thru a slider. Its pimped out like a log cabin so the stove fits right in, hence why I want to keep it. But what I was doing was cranking the room temp up to 80 and I had a couple of fans at the base of the slider blowing cold house air in...it actually worked very very well and the whole house would average in the 60's. This year I have ng so what I want to do is pretty much just heat the sunroom and have a pretty fire going with the stove. The slider is still open so there is still some house air exchange. The stove can bring that room to 70 fast...so if it's in auto it will short cycle and its on off on off all day...stupid. So what I did was put it in "maintenance" mode, start it in room temp auto then throw the switch to manual...its been working great. However, the stove is suppose to go to min burn instead of shutting down, to me it seems like it is as the flame is really low and only ramps up once in a while but I'm still using a bag a day which seems like a lot to me for a stove to be running in min for 90% of the day. So, finally, the question is what sets the min ESP temp or how is it determined? ...and yes I've read the "how your harman works" post. Right now I'm running:
Feed rate: 3.5
Ign: man
Temp: 70(4)
Blower: room temp (middle between L and H)

I've got about a 1" of ash at the edge of the pot, glass is clear, room temp is usually higher than set point....seems to be burning good. I think the stove could run lower when at min tho. So how do I get the stove to run at its lowest and keep the room at least 70? It just seems like a bag a day is a lot for how the stove is running/setup...just curious if I'm missing something or more detail on how the ESP is determined.
Btw burning oakie premium pellets and the stove does have a oak

 

[drmx]

The P-Series specs PDF lists the P43 feed rate as 1.9lb/hr min to 4.7lb/hr max.

24 hrs * 1.9lb/hr = 45 lbs per day

I'd say it is running as low, or even a little lower than minimum spec. How does the flame look? Probably just enough to maintain a fire. Feeding for about one 10-second cycle every minute? I'm not sure you'll get that stove to run any lower. I'm not exactly sure what the minimum ESP temp is, but it is probably high enough to avoid the fire going out, knowing there is no igniter to bring it back.

 

[P43pig]

The P-Series specs PDF lists the P43 feed rate as 1.9lb/hr min to 4.7lb/hr max.

24 hrs * 1.9lb/hr = 45 lbs per day

I'd say it is running as low, or even a little lower than minimum spec. How does the flame look? Probably just enough to maintain a fire. Feeding for about one 10-second cycle every minute? I'm not sure you'll get that stove to run any lower. I'm not exactly sure what the minimum ESP temp is, but it is probably high enough to avoid the fire going out, knowing there is no igniter to bring it back.

Flame looks good
Feeds for 8-10secs every 35-40secs

 

[alternativeheat]

Flame looks good
Feeds for 8-10secs every 35-40secs

If I had natural gas in my house I doubt I'd be burning pellets at all. If I wanted a stove in that room I'd probably sell off the P43 and get a free standing gas stove.

 

[P43pig]

If I had natural gas in my house I doubt I'd be burning pellets at all. If I wanted a stove in that room I'd probably sell off the P43 and get a free standing gas stove.

Yeah I know, but it's already in, works very well, have to run gas line and change the venting, have to buy another stove, etc... I actually have a gas fireplace and I never use it, I like the p43. I might just run it on weekends since it's just a toy now. $7 a day to run it...where it cost me $.76 to run my furnace an hour, and I only run 1.5 hrs a day right now to heat the house.

 

[drmx]

Flame looks good
Feeds for 8-10secs every 35-40secs

That feed rate sounds like ESP is calling for about a 1.5 feed rate. You could experiment with lowering your feed rate from 3.5 down to 1 and see if usage is reduced but still enough to keep the fire going. But you're still near the limit and have to decide if you want nice little fire all day or run in Room Temp to save pellets. Or just run weekends like you said.

 

[jackman]

I run my stove much like you do in room temp manual with a feed rate of 3.5 which burns about 1/2 bag/day. I heat a 1200 sq ft space. The only time the flame comes up is if the outside temp drops pretty low. Otherwise it's just a low flame maintenance burn.

I'll second drmx's comments and suggest you lower the feed rate to see how it acts.

 

[alternativeheat]

I've generally found my P61 in low heat requirement situations to use less pellets in Room Temp Auto than in manual when run 24/7. But that's a P61 heating 1800 sq ft, not a P43 in a sun room. People come up with unique circumstances and then the answer can't really be generic. I just know that pellets cost more than NG right now. Meanwhile so far this year I haven't used my stove at all and may not because oil is at or below the break even point, so why bother.

 

[bogieb]

If you left it in room temp/manual, then the ESP is not in play - it is using the probe only but being in manual, it can't shut down to save pellets, just go to lower feed rate.

ESP is used in stove temp (or constant burn - whichever your stove has). Try that at a low "temp" setting and low feed rate and with the blower on low. CoryS might drop by and give you some pointers too. However, it seems that the really new stoves are acting a bit differently than some stoves that are 2013 or older, but it is worth a try.

 

[alternativeheat]

If you left it in room temp/manual, then the ESP is not in play - it is using the probe only but being in manual, it can't shut down to save pellets, just go to lower feed rate.

ESP is used in stove temp (or constant burn - whichever your stove has). Try that at a low "temp" setting and low feed rate and with the blower on low. CoryS might drop by and give you some pointers too. However, it seems that the really new stoves are acting a bit differently than some stoves that are 2013 or older, but it is worth a try.

Actually on a Harman the ESP is always in play, it's just totally in play in Stove temp or so called Constant Burn. And playing a dance with the Room Temp Probe when running in Room Temp modes.

 

[TonyVideo]

Why put it manual room temp? You will save more pellets in auto. You could use an external thermostat and increase the setback so when in auto room temp it wouldn't cycle as much. Maybe 5 degrees instead of the Harman 1-2. You would have a 5 degree swing but it would cycle less. Quite possibly also turn down the feed rate to have it run cooler as we in auto mode so it would take longer to get up to temp.

 

[Cory S]

Flame looks good
Feeds for 8-10secs every 35-40secs

That's about a 25 second "ON" cycle time for the auger.... Auger cycle always rotates around a 60 second cycle. So if the auger is "ON" for 25 seconds, then it shuts off for an additional 35 seconds.

My findings in stove temp mode, is that adjusting the feed rate has far more effect than the temperature dial. If it's more than 43*F outside, I can not reduce the stove output enough, because it will get too warm in the house, unless I set the feed rate down to "1". Feed rate "1" allows the stove to have an auger cycle of 14.98 seconds "ON", 45.02 seconds "OFF". Any auger cycle "ON" time longer than 15 seconds will over heat my home. (We like it 67-68*). With these warmer outside temperatures, "Room temperature" mode would be more practical/efficient, especially with smaller heating spaces....(Normally)

I have pages of logged data on feed rate/temperature dial settings VS. Stove output air temperature and surface temperatures. You can not get the P43/P61/P68 down to the manufacturers minimum output of 13,000BTU, unless the feed rate is below 2.

 

[bags]

You can not get the P43/P61/P68 down to the manufacturers minimum output of 13,000BTU, unless the feed rate is below 2.

I agree. Sometimes I need to place the brick under the gas pedal here and govern the P68 down so it is comfortable in the shoulder season. Sure you can set it and forget it but at times I do not like the stove shutting down then starting and ramping up non-stop. Here consistency wins with me. I do get that. I also get others points of views on this matter.

As for pellet consumption running in different modes that is all merely speculation because to truly and accurately test this theory one needs a controlled environment with the same exact outside temps and conditions. The same exact inside conditions etc; The same exact pellets and so on. So to say anything about that is strictly ones opinion. Just say'in........

Bottom line is just do what works for you. Figure it out yourself because it is your stove, money, time, and creature comfort. Everyone varies a lot there too so again they are entitled to their opinions. This debate on how to run your Harman is much the same as which trucks and tractors are better. What's your favorite color? What is right for some can be completely wrong for others. One thing is certain. Many have opinions but when it gets cold, cold I feel most end up running with mostly the same settings in one mode or the other. This again is personal preference.

 

[bogieb]

Actually on a Harman the ESP is always in play, it's just totally in play in Stove temp or so called Constant Burn. And playing a dance with the Room Temp Probe when running in Room Temp modes.

Yeah, I know, the ESP is "always" in use, but for simplicity's sake might as well call it a non-player in room temp.

 

[alternativeheat]

Yeah, I know, the ESP is "always" in use, but for simplicity's sake might as well call it a non-player in room temp.

Watch and listen, anyone please :
<iframe width="720" height="396" src="https://www.youtube.com/embed/7x1I2Sr0fw4" frameborder="0" allowfullscreen></iframe>

 

[bogieb]

Watch and listen, anyone please :
<iframe width="720" height="396" src="https://www.youtube.com/embed/7x1I2Sr0fw4" frameborder="0" allowfullscreen></iframe>

And? That is all "this is magic so just believe us that it is awesome" marketing. At least when compared to what their claims are (within 1* - yeah, not with my stoves), and what I have experienced in reality. Yeah, the ESP does play a part, but the main factor, in my cases, is the probe and if it wants heat - it is either at full bore (for the feed speed), or at a very low idle, none of the in-between stuff.

Seems that not all stoves act the same, so I'm sorry if I stepped on a sacred belief.

 

[TonyVideo]

My 2 stoves keep the rooms they are in within 2 degrees easily. It works great. The flame will go up and down but not wildly. The colder out the more stable it seems to be.

 

[alternativeheat]

Yeah, I set it and forget it, My dining room stays basically 73 all winter when I'm burning. That is not a super sensitive thermostat thermometer in there but the swing is less on the stove than with the central heat. Just the central heat is just that ,central heat and so more even through out the house. And stove heat of course diminishes as you move to outer corners of the house.

Bogieb obviously has a different reality than that with her Harman stoves, she may not be alone. So be it, I don't come here to argue.. But the system is what it is, for me I have found it to work basically as advertised. It's designed that way after all, however there are varying conditions that can play into this. I for one have found the Room Temp Probe placement to be very critical. In this house with pretty cold floors in mid winter you don't want that probe to be near the floor. At the same time I don't have to worry about stack temps though because the ESP will take care of that, keeping it hot enough to not create creosote and never so hot as to have a melt down. Thank you Harman !

 

[jackhammer]

I agree. Sometimes I need to place the brick under the gas pedal here and govern the P68 down so it is comfortable in the shoulder season. Sure you can set it and forget it but at times I do not like the stove shutting down then starting and ramping up non-stop. Here consistency wins with me. I do get that. I also get others points of views on this matter.

As for pellet consumption running in different modes that is all merely speculation because to truly and accurately test this theory one needs a controlled environment with the same exact outside temps and conditions. The same exact inside conditions etc; The same exact pellets and so on. So to say anything about that is strictly ones opinion. Just say'in........

Bottom line is just do what works for you. Figure it out yourself because it is your stove, money, time, and creature comfort. Everyone varies a lot there too so again they are entitled to their opinions. This debate on how to run your Harman is much the same as which trucks and tractors are better. What's your favorite color? What is right for some can be completely wrong for others. One thing is certain. Many have opinions but when it gets cold, cold I feel most end up running with mostly the same settings in one mode or the other. This again is personal preference.

This seems to be a similar challenge to the one I'm having....