PB105 and PF100 burn pot hump and crack failure

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Has your Harmon PB105 boiler or PF100 furnace burn pot failed with a hump or crack?

  • NO - my PB105 or PF100 burn pot HAS NOT failed with a hump or crack.

    Votes: 0 0.0%

  • Total voters
    26
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exoilburner

Feeling the Heat
Dec 23, 2008
425
NW Washington State
Thanks for your help to find some answers to the burn pot problem in the Harmon PB105 boiler and PF 100 pellet furnace by participating in this poll. It seems to happen only to this burn pot. Same part number used in both units. The Harmon stoves don't use this burn pot and I've not seen any posts with this problem in their stoves.

The problem shows up as a hump forming in the middle of the burn pot air holes above the igniter location and deteriorates to cracks between the air holes. It seems to appear in my unit once or twice a during burning season. Other owners are also having this problem. But some are not. Maybe the reason for the difference can be found and a fix determined from the posts in this poll. Good information would be how owners run their PB105s and PF100s, settings, install, and what ever info. might help.

Please don't vote in the poll if your PB105 or PF100 is new and has not run for at least a full season.

It would be helpful to know wether or not you are having the problem and post information about how you run your unit.
 
Wayne64SS said:
Dude I voted no, but i looked today closer and there is a hump it's just not real big so i never noticed it. FML.

Wayne thanks for the vote. Keep an eye on your burn pot because thats the way it starts. First looks like a little warping in the middle of the burn pot air holes. Gets worse, forms a hump there over the igniter area, and starts getting cracks between the holes.

I have a picture of a bad burn pot and will post it if you need to see what this looks like.

If your burn pot gets the hump, vote again and let us know how you operate it, your settings and install info. Looks like nobody has figured out why this is happening on some PB105s and PF100s but is not happening on others. Need to figure it out before our warranties expire.
 
This is my 2nd season with the PB-105. I noticed a small hump developing towards the end of last season. It is now much more noticeable, and you can see the holes are starting to get larger ontop of the hump. My first ignitor burnt out after one season of operation in the automatic mode. Hope this helps, look forward to reading other responses.
 
ghangac said:
This is my 2nd season with the PB-105. I noticed a small hump developing towards the end of last season. It is now much more noticeable, and you can see the holes are starting to get larger ontop of the hump. My first ignitor burnt out after one season of operation in the automatic mode. Hope this helps, look forward to reading other responses.


Check out these two links for an ongoing discussion about the same issue:
http://forum.iburncorn.com/viewtopic.php?t=12709
http://forum.iburncorn.com/viewtopic.php?t=12779


Does your burn pot look like this one? Is the hump with enlarged holes in the same area of the burn pot?
If it looks the same could you post your settings, outside air, install setup, and how you run it. And any suggestions.

4picburnpot.jpg
 
I had just replaced my burnpot a couple of weeks ago. Boiler was manufactured in oct 2008. That was the original burnpot, lasted just over one year. I had waited until the bubble started to crack. If the bubble forms again, I will not wait that long!!!! The ignitor is located on the underside of the burnpot in my boiler. Still original ignitor. Run unit in auto mode all the time. Have the OAK and OAT both connected.
 
exoilburner,

My burn pot is no where near as bad as the one in the photo. I think mine is at the early stage of getting there. Attached are photos of my burn pot.

My settings are as follows:
Feed Rate 3.5
Low 145
High 165
Dip Switch #2 set to “ON” for slow feed rate on start-up.

I would think that the ignitor is causing the problem, because it is located directly below the hump. Maybe the heat from the ignitor during start-up is changing the characteristic of the metal, and then during normal burn the metal starts to break down.
 

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ghangac said:
exoilburner,

My burn pot is no where near as bad as the one in the photo. I think mine is at the early stage of getting there. Attached are photos of my burn pot.

My settings are as follows:
Feed Rate 3.5
Low 145
High 165
Dip Switch #2 set to “ON” for slow feed rate on start-up.

I would think that the ignitor is causing the problem, because it is located directly below the hump. Maybe the heat from the ignitor during start-up is changing the characteristic of the metal, and then during normal burn the metal starts to break down.

ghangac,
Nice pictures. I was having trouble getting a good shot of the hump (bubble). Although the hump in yours is small it looks like mine when it starts going bad. (Centered on the 5th, 6th and 7th row of holes) Thanks for sending your settings. Hopefully the PB105 and PF100 gang on the forums can find out why some units are having this problem and others are not. I think Harmon is working this issue too. Collectively maybe we can come up with some information that will help them. So far nothing stands out between the good units and the failing units that would give a hint about why some work and some fail.
I had an area rep looking at my PF100 and he was going to look at another PF100 in his area that had the problem.
 
I'm on my second burn pot. The first lasted the entire first heating season - 7 months and 6 tons of pellets. The dealer said the new burn pot I got was a PB105 burn pot and was supposed to be heavier steel and less likely to warp, but I noticed it's starting to hump up and I still have 2 months to go in this heating season. It does seem to be standing up a little better than the original. I use OAK in a basement.
 
To Exoilburner.............

It concerns me a bit when you post " Need to figure it out before our warranties expire." Harman is aware of this problem and has already provided warranty exchanges on multiple units. There should be no warranty expiration period for a known manufacturing defect that is under review. When or IF Harman figures out a solution for this, the fix should be provided free of charge to all PF100 owners. Furthermore, since Harman is aware of the problem, I think THEY should be the ones collecting data by contacting all PF100 owners with a questionaire or something to help get to the bottom of it. Don't get me wrong, I appreciate what you and others are doing, it's just that I think Harman should be more proactive. Their "arm's length" policy needs to be modified to fit the circumstances, and I believe that this case warrants them "coming out of their shell" and actually interacting with THEIR CUSTOMERS.
 
ex-oil slave said:
To Exoilburner.............

It concerns me a bit when you post " Need to figure it out before our warranties expire." Harman is aware of this problem and has already provided warranty exchanges on multiple units. There should be no warranty expiration period for a known manufacturing defect that is under review. When or IF Harman figures out a solution for this, the fix should be provided free of charge to all PF100 owners. Furthermore, since Harman is aware of the problem, I think THEY should be the ones collecting data by contacting all PF100 owners with a questionaire or something to help get to the bottom of it. Don't get me wrong, I appreciate what you and others are doing, it's just that I think Harman should be more proactive. Their "arm's length" policy needs to be modified to fit the circumstances, and I believe that this case warrants them "coming out of their shell" and actually interacting with THEIR CUSTOMERS.

Couldn't agree with you more. But, my dealer talked to the Harmon area rep and was told they were working on this but when an owner's warranty ran out the owner would be responsible for the expense of replacing bad burn pots. He was giving me the bad news.

This concerns me too; that's why I hope owners will be proactive and involved in getting this resolved. And give it some public exposure.

I have been considering sending a dated, "signature required" letter to Harmon to establish the fact that my unit had failed during the warranty period and that replacing burn pots was not the solution to a known design problem. The on going expense for this problem should be theirs not the owners. I'm going to talk to my attorney and find out how to do it right the next time I experience this failure.
 
ex-oil slave said:
Let me know what you find out. I'm willing to do the same from my end if there is any point to it.

Will do. After I talk to my attorney I'll post the info.
 
The Harmon area rep and my Dealer tech had been here to look at this problem. They suspected the igniter; I volunteered to run my PF100 without the igniter because I never use it. They removed the igniter from the burn pot.

I called the dealer today and informed the tech that after a month of running without the igniter the problem is still there. The hump is forming in the same place and in the same amount of time. My Dealer has a log going and is adding this information to it and will call the Harmon area rep with the info. He gets updates to the problem resolution if there are any and is good about passing along information. Will post anything new.
 
Found this post from wil on a poll on another forum that might be some good news. That poll is also related to the PB105 and PF100 burn pot bubble forming.

On 3/24 I replaced another burnpot, on 3/28 a bubble started to form on the new burnpot, I was really pi$$ed, went to see my dealer and mentioned that I thought it was time for Harman to make a burnpot using heat resistant steel such as in the link above. My dealer said he would contact Harman, mentioning to them my thoughts. I talked to him last week asking what Harman is going to do about the burnpot issue, are they going to make one out of heat resistant steel. He told me that Harman is going to manufacture one out of stainless steel, I'm in hopes that it is heat resistant stainless such as in the link below.
(next post)From what my dealer has mentioned, the new boilers even with the factory installed pressure ignition are having this same issue with burnpots. The thought from Harman was this pressure ignition was going to resolve the burnpot issue but it didn't so now they are going to make the burnpots using stainless steel. ( heat resistant I hope or they will continue to have this problem)

http://forum.iburncorn.com/viewtopic.php?t=12779&postdays=0&postorder=asc&start=45
 
UPDATE:The new stainless steel burnpot, ( the bottom surface only is stainless) was installed in my boiler yesterday, only time will tell if this is the answer to the "burnpot bubble" issue. The understanding that I have from my dealer is, Harman has made very few of these for testing to see if this is going to be the soultion and I was one of the chosen ones to test them. THANK YOU HARMAN.
 
How is the ss burnpot working for you?

I bought my PB 105 in August 07.
New burnpot in August 09 due to bubbles.
Now Sept 2010 and igniter will not lite. Was running fine for last few days but now refuses to ignite. May have to replace igniter.
Can you tell me about when u replaced yours and why? Should I be looking at replacing it with the pressure igniter u talked about?
Sorry for all the questions, have been out of the loop with the forums for a year or so and just catching up on the latest with PB 105.
 
rockymoses said:
How is the ss burnpot working for you?

I bought my PB 105 in August 07.
New burnpot in August 09 due to bubbles.
Now Sept 2010 and igniter will not lite. Was running fine for last few days but now refuses to ignite. May have to replace igniter.
Can you tell me about when u replaced yours and why? Should I be looking at replacing it with the pressure igniter u talked about?
Sorry for all the questions, have been out of the loop with the forums for a year or so and just catching up on the latest with PB 105.
The new SS burnpot after 3.5 weeks of use is working great. I'm checking it every week for signs of a bubble starting to form, to date it is looking good. The original burnpots, after 1.5-2 weeks of use I could measure a small bubble starting to form.

The pressure ignition that was installed in my boiler, under warranty, it was an effort to stop the burnpot bubble issue, it did not resolve this issue. The pressure ignition does ignite the pellets quicker which is a big plus. I suspect the pressure ignition conversion kit may be quite spendy if it was not covered under the warranty.
 
UPDATE #2 It has now been 7 weeks with the new stainless burn pot installed with NO bubble issue, just MAYBE this issue is resolved, I sure hope so, more time is going to tell.
 
New igniter $89.00. Boy does it light alot quicker. Time was cut down by better than half. I put it in myself about 3 weeks ago and it is working great.

We are averaging 10-12 ton a season to heat a 2400 square ft home with vaulted ceilings. My wife is home all day long and keeps it 74-75 degrees.
 
wil said:
UPDATE #2 It has now been 7 weeks with the new stainless burn pot installed with NO bubble issue, just MAYBE this issue is resolved, I sure hope so, more time is going to tell.

wil,
Thanks for the updates. I'm sure many of us are following the news about your new burn-pot. Have you heard anything from Harmon about your results?
 
wil,
Thanks for the updates.  I’m sure many of us are following the news about your new burn-pot.  Have you heard anything from Harmon about your results?

X2
 
I've operated my PB105 for a year now and burned 7 tons (to supplement my FHW Oil, Hearthston woodstove and Russian fireplace) of Ashland Maine pellets (factory burned down last year). I would never have noticed the bubble and cracking if I hadn't found this forum. I just checked and sure enough my burn pot is in the early stages of the bubble and has 2 small cracks connecting 4 air hoes. I found the easiest way to assess it is shine a good flashlight horizontally across the surface and eyeball across the surface and you can easily see what, in my case, I could only feel. Mine was manufactured 8/08, installed 10/09, I run on auto at varying feed rates (I'm a fan of 6 though). No outside air or temp connected. I'm on my original igniter BUT my auger motor locked up and was replaced.
 
UPDATE #3: Doing the weekly cleaning today I noticed the stainless burnpot developed a bubble along with a crack between 3 holes. I don't believe the burning surface of the burnpot made from stainless steel is the answer to the burnpot issue. The burnpot has been replaced with the original mild steel one, not the stainless one. My dealer is shipping this one to Harman to evaluate, I hope I have more info after they inspect it.
 
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