My pellet stove sucks.....

  • Active since 1995, Hearth.com is THE place on the internet for free information and advice about wood stoves, pellet stoves and other energy saving equipment.

    We strive to provide opinions, articles, discussions and history related to Hearth Products and in a more general sense, energy issues.

    We promote the EFFICIENT, RESPONSIBLE, CLEAN and SAFE use of all fuels, whether renewable or fossil.
Status
Not open for further replies.
I'll PM you, Mike, re: grad school- you'll get a kick out of it! Seriously, the next time we run for 24 hours straight for a few days, I will pay attention to how many times we feed the stove. We don't let it burn down to an empty hopper every time, or even down to where it will take a full bag every time. We fill the hopper every day during burn season, and most often we have a partial bag left over- but we don't necessarily fill it at the same time every day. In other words, I have been less than scientific about it. We haven't yet burned a ton this season, but we are coming up on it. I'd estimate that we have burned about 40 bags of pellets since the end of October. Husband concurs. That's just about right- we haven't hit the coldest part of winter, and we typically burn about 2 tons a season if it's cold.
 
Glad to see Glocke is still around after a couple of forum 'members' acted like @$$holes. Maybe the mods can come in and give a few spankings and clean up the thread a little bit.


Welcome to the forum Glocke, stick around the majority of the folks here are great and will help you the best they can. With a little trouble shooting i think you will be up and running 100% in no time.
 
no worries, my questions are to help me develop a theory which may help the OP figure out his issue. there's a method to my madness. rather than make suggestions first i prefer to look at symptoms based mostly on my knowledge of general operation and theory of pellet stoves, then try to put the information together to give a potentially more accurate suggestion.

not knowing all of the operating systems in my competitors stoves is a bit of a handicap to me, but i understand the dynamics of how they generally operate very well, and i understand fire and what it does to air. spent the better part of 20 years learning this. helps that im addicted to fire in general, controlled fire specifically. i've actually sat and watched campfires trying to pick out why a certain part of it isn't burning as efficiently as another. silly i know, but fascinating at the same time
 
  • Like
Reactions: Bob Sorjanen
glocke12 and stoveguy2esw, I just wanted to let you guys know that we are working on timing out a 55 lbs. hopper full of pellets vs. a feed setting of 4. Right now we are about 25 hours in, and we have, by my visual estimation, about 10 lbs. left in the hopper.

We're staying in tonight; we did everything we've ever wanted to do on NYE years ago. Now we are happy to stay home in our warm, comfy house, with our furbabies, eat a great meal and let the partiers have the roads after midnight. :):) I should be able to hop back on later and give a more accurate lbs/hour rate when the hopper is close to empty.

Happy New Year, everybody! :)
 
well, if your "eyeball" guess is accurate you are at 1.8 lbs/hr which is a 24 hour bag. kinda low in output our units run at about that rate on h/r 1 of 9 up to 5 lb/hr on high. interesting wonder what that stove feeds on its lowest range not asking for a test run just thinking aloud with my fingers ;)

hope you folks have a happy and prosperous new year, good of you to take the time to run this test to help out our OP
 
This is what remains in the hopper as of a few minutes ago. We started this burn yesterday at about 6:15 pm with a full hopper. That would be about 26 hours ago. The hopper holds 55 lbs. According to the manual, burn rate is in pounds per hour, and is listed as 1.0 to 5.0 on the specs chart. (I guess I never read that chart closely enough until right now- it clearly states: "Burn Rate (Pounds per Hour)** 1.0 to 5.0
** Small pellets will increase or decrease the stated burn rates and burn times. Differences of plus or minus 20% depending on fuel quality may occur."

So, at the recommended setting of 4, the stove should be, optimally, burning 4 lbs./hour, or a bag every 10 hours. In my experience, we have never burned two full bags of pellets in a 24 hour period. I just don't remember it that way, and today's trial isn't showing that either.

To further fill out this picture, we were away for the weekend. We left the stove off and the heat turned down while we were gone, so we came home to a cool house. We came home after dark, bumped the HVAC thermostat up and started the stove from cold, clean and full. We are using it to heat/supplement 1420 sq ft. The natural gas furnace ran for about an hour or so to bring the house up to temperature, aided by the pellet stove. The HVAC thermostat is in the hallway, immediately outside of the doorway to the room in which the stove is installed. The HVAC return is high on the wall, near the ceiling, in the same hallway, above the thermostat, right outside of the stove room. When the HVAC is on, it pulls stove heated air out of the stove room, across the thermostat and into the return above. It didn't take long to bring the house, or at least the hallway and the thermostat, up to our desired temperature. The heat distributed through the house fairly quickly as heat follows cold and we have a circular floor plan, with the stove blowing out of the doorway and into the L-shaped hallway in that circle. The HVAC cut on once or twice more last night, briefly. It fell to freezing quickly, and we had overnight/early morning temps in the 20's. The HVAC cut on again this morning, once, and hasn't cut back on today.

It's been cold to cool today, and overcast, which is a factor with our brick and block house. We have no wall insulation besides our brick, block and plaster mass. The attic is well insulated, as is the underside of the floor. We have a south/southwestern exposure and that lends a lot to thermal gain when the sun is out.

The house stayed cool today- about 65'F, right at the setting on the HVAC thermostat. The heat didn't kick on, but "just barely."

According to the Napoleon's owners manual, the stove is rated to heat 800 to 2000 sq ft, and should produce 8500 to 42,500 btu/hour.

I am stating all of this info here again, together, because one of the questions appears to be, are these Napoleon stoves putting out the btu's as advertised? We've always put the blame for any "lack of heat" on our lack of wall insulation, and initially, on less than optimal attic insulation. We've since beefed up the attic insulation and that has helped. We can't do much about the lack of wall insulation other than skim coat the entire exterior of the house- and we aren't doing that.

A couple of years ago we were at our stove shop, and they had a pellet stove running in the shop. As in glocke12's experience, we were surprised at the heat that stove was putting out. We remarked that our Napoleon didn't seem to put out as much heat as that stove. The salesman said that the stove was running so hot because it was set on high feed and was burning through pellets at a remarkable rate. Btu's in = btu's out. Most people wouldn't run their stove on high like that in an every day situation.

That particular shop stocks Travis Industry pellet stoves now. They no longer carry Napoleon pellet stoves. I don't remember the name brand of the stove, but I remember that it was a large free-standing pellet stove, and given that the shop carries Travis Industry products, I'm betting that it was an Avalon.

Yeah, I guess I'm a little surprised that we aren't eating through more pellets at a feed setting of 4, which should be 4 lbs./hour, but apparently is not. Makes me wish that I'd read that chart more closely and that I'd done the calculations while the stove was under warranty. What could or should we do about it now? Is it a pellet thing, or a feed thing? And how to tell the difference?

I know that the manual recommends a feed setting of 4. I can find that in the manual with no problem. Somewhere, some time ago, I seem to remember coming across a piece of information that stated that the stove should not be run on the highest feed setting of 5 for more than one hour at a time. I cannot seem to get my hands or eyes back onto that piece of information- I can't track it down. Suffice it to say that I am reluctant to run the stove on 5.

So other than putting in super high efficiency hot burning pellets, how can we squeeze more btu's out of this stove? What to do about the lbs./hour feed issue, if anything?
 

Attachments

  • 007.JPG
    007.JPG
    133.8 KB · Views: 192
Well it might surprise you Beca but Mike and I have discussed a few things about what happens in relation to the vacuum switch and the gaskets on the stove (and this would apply to just about any stove).

It turns out that as the fire builds the air density drops in the firebox, if this drop goes low enough the vacuum switch opens cutting some of the feed, this leads in a slight drop in temperature and and then increases density in the firebox which then closes the vacuum switch allowing pellets to feed again. Provided the vacuum switch doesn't stay open for too long the controller doesn't signal a vacuum fault and shut the stove down. The end result is actually a varying feed rate that would tend to push the effective feed rate toward the lower end of the scale instead of the higher end.

Anything that can replicate the pressure difference at the vacuum switch can also do the same thing if it is cyclical.
 
Huh. Interesting. I know that the combustion motor gasket is practically brand new. I changed it out about a month ago myself, when I pulled the combustion motor and did a thorough cleaning. We burned a little bit last year after the last "big clean," and we started burning this year before another "big clean," so I just did a "big clean" about a month ago, a little off schedule but it was done. I swapped out the combustion motor gasket at that time because the old one came apart at the screw holes when I pulled the motor.

We noticed, a couple of weeks ago, that the rheostat on the convection blower was acting up. The convection fan would not run on settings lower than 5, or high, if it was turned on manually with the knob and turned straight down to a setting lower than 5 or high. In order to get it to run, one had to turn it back to 5, or high, and then the fan would cut on. Once the fan was running, one could then turn it down and it would continue to run.

My husband pulled the side and examined the convection fan. It turned easily by hand, and it was clean. Clean didn't surprise us: I pulled that side of the stove off and vacuumed the convection fan when I did the big clean a month ago. Not to brag, but our convection fan has never been dirty, not even dusty. With a Labbie, a 20 lbs. cat and two adults living full time in 1420 sq ft, plus various friends, family and family pets in and out, we vacuum daily. I'm not being virtuous; it's a matter of basic hygiene. So the convection fan was not dirty or dusty. BUT, my husband pulled it anyway, and vacuumed the housing behind it, and oiled it in the oil ports. When he did, the convection blower gasket split at the screw holes. We didn't have another convection blower gasket at the time. We decided that since that was not on the "fire" side of the stove, it would be OK to piece the split gasket together in between the convection blower and the housing for the intake, being careful to make sure that the gasket ends abutted, and secure it with the screws.

We've been running it like that since with apparently no trouble... we ordered new gaskets to replace the split gasket, and a new rheostat. The gasket and the rheostat have arrived, and in keeping with our Pellet Stove Maintenance on Holidays mantra for this year, we were thinking of replacing both tomorrow.

The convection blower is still working, albeit it is now making a slightly louder, cyclical motor hum on occasion, so we are betting that we will be replacing that convection fan as well. Debating whether or not to go ahead and order one now, and just have it here...

Anyway, could the split in the gasket on the convection blower side contribute to a drop in pressure in the fire box, thus interrupting/limiting the pellet feed, despite the feed setting? Would a gasket split on the CONVECTION blower side do that?

And no, it does not suprise me one bit that you and Mike have discussed fire box pressure vs. vacuum switches vs. gaskets!
 
We weren't talking about the combustion blower gasket as much as about the OP's door gasket not passing the dollar bill test.

I can walk three bags of pellets a day through my stove no problem at all it has a similar firing rate range as your stove has and my hopper is also a 55 pound (such as poundage counts for much) unit.
 
There is no way that we could put three bags of pellets through this stove in a 24 hour period. Huh. As soon as I typed that whole thing out, and was repeating it to my husband, it occured to me that y'all were probably talking about door gaskets rather than blower gaskets. Our gaskets passed the dollar bill test at the end of last year. Admittedly, I haven't done it this year. I will do it at next shut down. I don't suspect that's a problem; our stove is burning too cleanly, too brightly for a door gasket issue.

I'm going to try to put my hands/eyes back on the blurb about not burning the stove on high for more than an hour. I can't find it now, but I swear I thought that it was in the manual or in some other verifiable, reputable source. Gonna go find it now.

Thanks again for thinking through this with me, Smokey- you have always been a great resource!
 
looking at that picture i see what appears to be maybe a third to a quarter bag (hard to tell accurately as i do not have (nor do i need) the dimensions of the hopper, it ain't that important sweetie.

anyway for starters your "convection" (aka room air) blower gasket has nothing at all to do with anything, its usually there more for noise absorption than anything.

im shuddering now as i hope i haven't opened a can of worms with you guys, i am assuming you have been satisfied with your stove and i don't want to displace that with any fear it isn't working right.

i look at hard numbers a lot. i know roughly what a pound of pellets contains as far as BTU "potential" so looking at what is contained i extrapolate a reasonable approximation of what one gets into the room based on fuel spent per hour figuring on complete combustion. this is what has interested me in your little experiment. see for every pound of fuel you burn per hour (assuming you have complete combustion) you release about 8500 BTU of stored energy, from that you should be extracting roughly 6300 to 6800 BTU in realized heat depending on the efficiency of the heat transfer system of your stove, the rest leaves with the exhaust.

the amazing part is that the actual output of the stove at 1.8 lbs/hr is roughly 11394 to 12240 btu/hr, yet it is doing a proper job in maintaining the heat load in your home. this is a good thing as its very economical to run a bag per 24 hours.

now , take a lesser insulated structure, you may not be able to actually heat the structure with that output. heat ain't magic, its physics. heat cannot be destroyed , once created it can only be dissipated which happens when the thermal energy is distributed to colder molecules from warmer ones. the amount of dissipation depends on a delta of sorts the difference in temperature between one particle of air or solid compared to the ones which surround it. the higher the delta , the more robust the dissipation rate and thus the lesser realized gain in overall heat of a space or solid.

bear in mind im stretching the ability of my beer soaked brain to lay this out , but ive re-read it a few times and im thinking ive got the theory nailed as far as laymans terms. its complicated in mathematical terms but in practice its simple

take an ice cube, sit it in a room with a constant 70 F temperature, it melts at a certain rate due to the "delta between its surface and the surrounding air. heat is dissipated at a given rate based on that differential. now take the same ice cube, put it in a room which is sustained at 60 F the delta is smaller so the rate of dissipation is slower hence the ice melts slower the ability to gain heat works the same way, the gain rate changes the delta (the air in the room being the ice and the stove being the room in this case) since the room doesn't sustain a lower temp due to higher insulation factor the gains are higher, in a room where the heat is dissipated at a higher rate due to lesser insulation the dissipation rate is higher and the room doesn't warm as fast if at all.
 
No problem, Mike, and thank you for responding- you're not raising any doubts or questions that we haven't already entertained, especially when we discovered that Avalon apparently putting out more heat.

It's not unusual to fail to recognize blessings (in this case, apparently, the btu's generated are mostly staying inside the living areas of the house, i.e. we are retaining the heat produced) when one doesn't yet fully understand the math and the physics involved in the equation.

After four years of pellet stove ownership I will freely admit that I'm still on that learning curve. I understand the form and function better now than I did when we started, but I will freely admit that I'm still learning the finer points and even some of the simpler points. It never occured to me until today that maybe I need to know *exactly* how many pounds we are burning an hour, and what that does for the btu output- simple but I just never thought about it before. On the other hand, as you've pointed out, if we are extracting enough heat to maintain and even raise the temperature in a 1420 sq ft house by burning just under 2 lbs of pellets per hour, we don't necessarily have a problem, we might just have a really efficient stove, or a well-enough insulated house, or some combination of both.

I know that previous issues with maintaining the heat in the house were directly related to inadequate insulation in the attic. Adding insulation in the attic made a HUGE difference. Thermal curtain panels over the cell shades over the double paned windows blocked convective cooling that we experienced around the edges of the cell shades a couple of winters ago, during that long stretch of sub-freezing temps both day and night, and thick area rugs on the wooden floors helped as well. Since then the pellet stove has carried the house much better.

Nevertheless, if Napoleon says that a feed rate of 4 equals 4 lbs. an hour, then the feed rate at 4 should be somewhere around 4 lbs. an hour. Even allowing for the 20% decrease in feed rate with small pellets, as noted in the owner's manual, we should have a burn rate of at least 3.2 lbs. an hour, or about 3 lbs. an hour- or 72 lbs. - 76.8 lbs. in a 24 hour period- or two bags in 24 hours. We've never burned through two bags in a 24 hour period during a continuous 24 hour burn.

Right now we are at 28.75 hours and there are *still* pellets left in the hopper, see below. Not many, but the hopper isn't empty yet. I bet we hit midnight, 30 hours, before we burn through 55 lbs.

So, to answer this question, I have sent an email to Napoleon, asking about this discrepancy. I think it's a fair question.

I'm a bit of a physics geek (I understand delta T and heat dissipation) and I'm married to an IT geek. We love numbers. :) :)

To that end, see my highly scientific candy thermometer stuck in the far left convection blower outlet, the "hot" side, of the stove. When I took the pictures, the thermometer read about 325'F. Right now it is at 310'F, but a few minutes ago, it was at 330'F. I guess the temp is varying with the height of the flame in the burn cycle. At any rate, I can't complain about a temp output of over 300'F, regardless of feed rate. :) And the temperature in the house is rising, without any assistance from the HVAC. Again, can't complain!

Thank you again, Mike and Smokey... and glocke12, if you are still out there, I hope this discussion is helping you parse through the variables with your stove and set up... don't give up on it!
 

Attachments

  • 013.JPG
    013.JPG
    92.5 KB · Views: 194
  • 010.JPG
    010.JPG
    118.4 KB · Views: 195
  • 011.JPG
    011.JPG
    101.9 KB · Views: 177
I have never been able to run a bag through any faster than one in 12 hrs.
My home is insulated and sealed. storm windows on the thermopane windows and even on the atrium doors. Double entry way used duing the winter. The way to get more heat from a properly maintained stove is to insulate the home at every point possible. Lots of ways to improve the insulation. We did it on ours and now get pay back every winter.
 
Save$, I'm curious- when you are running through a bag in 12 hours, what is your feed setting? (And have you ever run across that mysterious blurb about never running your stove on high, or 5, for more than an hour, or did I dream that, like I'm beginning to think I did???) I'm sitting on feed setting 4 at hour 29 on one 55 lbs. hopper full and I still have pellets in the hopper. Not many, mind you, but it ain't empty yet.

Boy, *we* know how to have fun on NYE! :)
 
  • Like
Reactions: stoveguy2esw
Status
Not open for further replies.