Performance Loss P68

All right update on the stove as I have had a little bit of time to change a few things out and since then I have realized my problems were not explained clearly before. At some point I am going to try to jump on the phone with Badbob as my problem is identical to what he was experiencing with his sisters stove. Time difference and the mental amount of time I have to devote to work along with normal chores around the house.
As bb explained if I turn it all the way up it cranks up as it always has but any lower settings it just has a lower flame and the ash line sits back almost 1 1/2"- 2" from the edge of the pot.

What I have replaced so far is auger motor, circuit board (replacement on the shelf now) ESP probe and last year end of season replaced the flame guide and new door gaskets both hopper and ash .
Really strange behavior as it will run normal for a while then revert back to running wonky but the ash line never makes it out to where it was the previously 3 years. No lazy flames always hot burn but much lower than what it use to unless I crank it all the way up, I know my stove very well especially seeing that I never run it in room temp mode always constant as I pay close attention to the weather and set the stove accordingly for the day while I am away at work for 14 hours.

Thanks again for the support at some point I'll get Badbob on the phone.

 

Luney your problem really sounds like fuel starvation. Did you look at the link I provided earlier on in this thread? While the title of the thread is about P68 slow startup, I was also having exactly the same issue you appear to be describing here, and at the end of all the troubleshooting - it was simply due to not getting enough pellets into the burnpot, due to a worn part causing the slide plate to not move it's full range of operation. Replaced the worn part (and in my case, the slide plate too). The smallest things can make a huge difference. Take some time to read it and see if anything there applies to you, could be a real quick fix.

Also be very cautious about judging how the stove is operating based on how far back the ash line is. That 1" guideline is nonsense. For me, the further back the ash line is, the better - and I find the better the quality of pellet you are burning, the further back the ash line will be. If you have a stove pipe temp gauge on the side of the stove, that is a much better indication of the real heat you are getting from the stove, because you know for sure how hot the stove is, regardless of flame size or ash line position.

 

Thanks man Ill check it out again when i have time argh !
I am basing the ash on how the stove has operated the previous 3-4 years and I do understand about the pellets and even burned a few bags of MWP to confirm, same outcome.
I pay close attention to the operation of my stove and it drives the wife crazy and she chalks it up to my OCD, but have always been this way with mechanical devices. I also have a temp gauge which is always been apart of my monitoring stove operation going back 30 years with being a wood burner all my adult life.

Headed down to spend some time with Mom and Pops, going to be watching some football every game on as it is a passion for my father and one of the only reliefs for his constant chronic pain. He has NFL pass , red zone , and whatever else is available so you end up watching every game all at one
Good stuff
Thanks man

 

Nothing wrong with OCD. That being said, dont stress too much about where that ash line is. In constant burn, the amount of feed will be based on what temp the ESP is reading and less so on your feed rate. Things that would affect this is the pellet, minute changed in the temp setting on the dial, cleanliness of the ESP and stove, variations in voltage to combustion fan (line voltage), etc......thats too many variables to attempt to recreate them all and get a constant line. You cant control the pellets, which easily can vary year to year (and batch to batch even!), even given the same brands....

 

That is for sure yesterday grabbed the last ton of Vermonts and these are not like any that I have ever gotten including some this year from another vendor, extremely hard and blonde and very little to almost no pine scent what so ever. Hoping this is not the batch someone spoke about earlier , will see how the toast.

 

Must be the bad batch as they burned up in no time last night and did not put out the awesome typical Vermont heat ......
Bummer

 

yea, this can happen with ANY brand, sad but true. That GREAT pellet you tried last year might be totally different this year!

 

If you got a legit bad batch, contact VWP and tell them, they will definitely want to know. They have pride in their product and take customer satisfaction very seriously, and will want to address the situation.

 

If they really do, they should send him a voucher for a replacement ton.

 

Cannot add anything here that has not been pointed out a few times but can you explain "overburn" which the OP mention he does not let the stove do...

 

Perhaps you mean over fire ? With wood stoves its more prevalent but it means firing(running) the stove at its max possible for extended period of times. Don't think it is as common with pellet stoves but with wood stoves loading the firebox to the max repeatedly to keep the fire at the hottest possible temperature and the stove operating at the hottest temperature obtainable for extended periods of time. With wood stoves or older wood stoves they will reach a temp that they actually become cherry red which is extremely dangerous and yes I have done so and am guilty of , they can warp and worse case collapse as the stove becomes molten metal.

I remember when i sold firewood in upstate NY every now and then apple orchards would want old trees cleared and it was pretty east to process as there was little splitting so buck load and sell. Probably not in this specific forum but I am sure some have burned seasoned apple wood it burns insanely hot so when we came across one of these situations where we would harvest some we would strictly warn the clients of this but one did not listen and actually burned their house down over firing their stove.

Pellet stoves not as susceptible as they do not reach the temps that wood stoves can but my stove the P68 wide open will easily reach 550* with good pellets and everything cranked all the way up . So with pellets stoves I would consider running them at their max for extended periods of time to be over firing as there are a lot more of moving parts that may not be able to withstand this constant excessive heat . As mentioned I do run my stove's very hard but feel I am not over firing them to the extent that I am damaging parts.
With wood stoves (older wood stoves never owned a cat stove) cranking them up burns off creosote that could be created by less then optimally dried wood or dampening down the stove to early .

Open to corrections and comments
Thanks

 

For perspective, our P68 at feed rate 3 in room temp mode and under max heat demand will regularly reach 550 degrees, as measured by a heat gun and a stove pipe temp gauge attached to the side of the stove. It will at times reach 600 degrees as well, and at that temperature, we get the telltale "the stove is too hot" smell, which I equate the the over fire condition you describe with a traditional wood stove. I think anyone who has burned a wood stove for years will be familiar with it. Anyway, when the P68 stove body reaches 600+ degrees, not only do you smell the smell, but the stove is so freaky hot, it's scary and uncomfortable to be near it - wife calls it "burn your skin off" heat. For this very reason, I have the feed rate turned down to just a hair below 3 to stop the stove getting that hot.

 

TT read through your entire thread you linked and at some point when time presents itself I can apply it to my continued pursuit to have my stove operate as it once did .

Thanks

 

So,reading all this, appears to me peoples expectations are involved. People expect certain outcomes,from their own experiments. The newest Harman control board seems to me that the temperature ranges are lower(safety,), my Integra is the same way,with the latest Prom livable for that unit. Does it put out less heat?? No it just comes in slower,yet over time is a more controlled,even heat. Perhaps this is what Harman has done?. My sisters Harman(p68) up in kallispell, has been doing awesome, since I went up there and resurrected the old unit.I think some people forget items,such as heat output,"how it was when I was younger".

 

Yup, I remember walking in 3' of sn*w to school, uphill both ways.

 

Well one thing very positive that came out of replacing the circuit board is the room temp mode is working perfectly and the stove is keeping the shack warm.
With the old board it was very erratic and really did not work to well hence the reason I always ran my stove on constant burn mode. Going down to 15* tonight which is not super cold but in this poorly insulated house it gets chilly so this will be a good test but so far it has been working admirably.
Gave both the stoves a good cleaning today which always helps but especially with the P68 so I am going to sip some fine Bourbon to celebrate, this will be really nice to just let the stove do its thing just have to add pellets.
And perhaps burn less pellets now that would be nice.

One thing I did notice was when the stove was nearly empty after shutting it down I could push the plate manually about another 5/8" and more pellets dropped . Dunno see what happens just happy I had time today to give both the stoves a good cleaning and room temp mode is working flawlessly...

 

What's your choice for (fine bourbon)?

 

Blanton, Basil Hayden, Willett, Angel's Envy, Calumet Farm, Redemption to name a few there are many more but a bit foggy this morning . How about yourself ?

 

Some manual slide plate movement is normal. Not sure about 5/8 inch, but the fact that you can move it is expected. TBH - that was one of the main hints that our P68 was fuel starved. Moving the plate back and forth manually yielded pushing a LOT of pellets into the auger chute that otherwise would not have dropped on their own. Another thing that helped was Subsailor telling me at startup time, his pot would be overflowing with pellets if it took as long to startup as ours was, when ours had barely reached the point of being over the igniter. Observed closely from the back and saw that the pusher arm wasn't moving the slide plate nearly as much as it should have been on it's own, because it was worn so badly. Having another similar stove (P43) to compare to helped to confirm 100% as well. In the end, the stove was moving maybe about 1/2 of the pellets per auger revolution as it should have been.