Empyre Elite boiler corrosion

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logger6644

Member
Jan 30, 2013
61
Upstate New York
I purchased an Empyre Elite 100 wood gasification boiler in Dec. 2010. with use beginning in the 11/12 heating season. I developed a boiler leak in Jan. 2013 due to creosote corrosion. In the attached photo, the area that failed was near the front right just below the side row of firebrick. The cutout shows roughly the extent of the corrosion and clean appearance of the inside of the tank.(my water tests were perfect) Damaged area and air duct.jpg I believe the corrosion was caused by creosote formed in the upper burn chamber flowing down the inside wall and accumulating behind the firebrick. Just below the damaged area is a duct directing air to the secondary burn chamber and you can see it has an opening at the top which allows air to escape behind the firebrick. I believe this oxygen source combined with the creosote is why the corrosion was so bad in this area. Has anyone else seen this problem? If you own one of these units, I would suggest you check under the firebrick in this area next time you shut down.
 
Wow, thanks for sharing. Did you notify manufacturer? any response? You need heat so weld that up asap.
 
Got a pic of the corroded piece?

I had been just leaving my primary chamber with a good build up of ash all over and not bothering to clean it out - but after more reading on here & thinking about it more I started a couple weeks ago also scraping the ash away from the outside bottom edges of the primary chamber (i.e. away from the firebox walls) and down into my secondary while cleaning my secondary out every day or two, while still leaving a good layer around the nozzle and on the floor of my firebox which is ceramic. That makes for a kind of a hump of ashes on the bottom, but I think I'll keep doing it that way.

Good luck with the fix - looks like it might be hard to get a decent waterproof weld all the way around that.
 
Wow, thanks for sharing. Did you notify manufacturer? any response? You need heat so weld that up asap.
I had been in contact with the manufacturer since shortly after I started it up in the fall of 2011 and was not getting the output and seemed to be getting too much ash and creosote. They initially responded with maintenance and operational advice. When that did not clear up the problem they admitted they had made a change to the air gate and sent me some drawing so I could update my unit. When halfway into my second season I discovered a leak, the manufacturer offered to pay for a welder. I was expected to do all the other work. When I disassembled the inside of the boiler to find the leak, I discovered layers of creosote everywhere under the firebrick and a duct that was supposed to direct air to the secondary burn chamber also directing air under fire brick in the area of the leak. The wall thickness was reduced from .134 inches to .020 inches. The opening in the top of the duct also allowed creosote to clog the air duct impeding the flow of air to the secondary burn chamber. So far no response as to how to deal with these underlying causes or reason why they are allowing air to be channeled under the firebrick.
 
Got a pic of the corroded piece?

I had been just leaving my primary chamber with a good build up of ash all over and not bothering to clean it out - but after more reading on here & thinking about it more I started a couple weeks ago also scraping the ash away from the outside bottom edges of the primary chamber (i.e. away from the firebox walls) and down into my secondary while cleaning my secondary out every day or two, while still leaving a good layer around the nozzle and on the floor of my firebox which is ceramic. That makes for a kind of a hump of ashes on the bottom, but I think I'll keep doing it that way.

Good luck with the fix - looks like it might be hard to get a decent waterproof weld all the way around that.

I have a welder who says he can do it, although it looks hard to me too. If you look at the area I cut out, the parent material on the left of the hole is 10 GA (.0134in). At the top of the hole in the middle it is .020in. The inside is unblemished. The main problem seems to be the shape of the inside firebox which tends to funnel any creosote behind the firebrick. Seems to me there should be some type of drip edge that would direct it on top of the firebrick where it would be burned off. Thanks for the interest.
 
There are several reasons to install storage but if there were only one, this would be it.
 
Wow, I'll be giving that a close look when I clean the boiler out during today's warm spell.

logger where are you located?
 
The video makes a few excellent and key points, which have been mentioned multiple times in many posts in this forum. 1) Need for return water protection: cool water in the boiler prevents the formation of protective creosote/tar coating in the firebox, allowing water to condense on the steel surface and corrode (water + creosote = acid = corrosion). Strive to maintain return water close to 160F (some boiler mfrs indicate 140+ is OK). 2) Long periods of idling, resulting from overloading based on low heat demand: results in creation of a lot of creosote in the firebox, accumulation and recycling of moisture = corrosion. Adequate storage can address this by allowing large wood loads to burn at full rate with excess btu's stored. 3) High moisture content wood is not good: implied from the video. Need well seasoned wood. 4) High acid wood is not the best: oak, for example. Probably should limit use and mix with non-acid woods.
 
So far things are looking all right in my boiler. Just fired it back up after a cleaning and inspection.
For some reason I can't get the video to play. Is it avaliable some where else so I could view it?

Logger, what are the last three digits in your serial #
 
Wow, I'll be giving that a close look when I clean the boiler out during today's warm spell.

logger where are you located?
Hi, I'm located in Canandaigua NY, in the Finger Lakes region. I bought my boiler in 2010. In March of 2011 they made a change to a part called Air Gate which affects the amount of air to the secondary burn chamber, but neglected to tell me about it until my persistant complaints about poor performance elicited a change procedure in Dec. 2011. By then I think the problem had compounded itself by causing creosote and debris to find it's way though the top opening in the duct, obstructing it, although at the time I still did not know where this air duct was or that it should be checked and cleaned. Their engineer said the duct was left open for cleaning but there were never any indication of the location or any cleaning procedure for this duct. He says there is a procedure in the works now and he is recommending the addition of 1 1/2" holes in the flat side of the duct for cleaning. He also agreed with me that it would be a good idea to block the top access hole with a patch sealed with high temp silicon so it could be removed. By removing a few of the fire brick in the area you will find the duct. Check it out and keep it clean. I'm still working with the factory to resolve the issue, but once I do I'm also going to add a drip edge to direct any creosote formed in the upper chamber over the firebrick where it could be burned off and not allow it to get behind the firebrick. If your boiler was purchased prior to March 2011,I'd check with the factory regarding the air gate modification.
 
The video makes a few excellent and key points, which have been mentioned multiple times in many posts in this forum. 1) Need for return water protection: cool water in the boiler prevents the formation of protective creosote/tar coating in the firebox, allowing water to condense on the steel surface and corrode (water + creosote = acid = corrosion). Strive to maintain return water close to 160F (some boiler mfrs indicate 140+ is OK). 2) Long periods of idling, resulting from overloading based on low heat demand: results in creation of a lot of creosote in the firebox, accumulation and recycling of moisture = corrosion. Adequate storage can address this by allowing large wood loads to burn at full rate with excess btu's stored. 3) High moisture content wood is not good: implied from the video. Need well seasoned wood. 4) High acid wood is not the best: oak, for example. Probably should limit use and mix with non-acid woods.
Thanks, all good comments, but I had gone over all these issues with the Pro-Fab engineer, and eliminated them before they finally shared a modification they had made to the boiler after I purchased it that affected the amount of air to the secondary burn chamber. In my case the problem definitely started with this design shortcoming. The Pro-Fab boiler has a 140F pump shutoff but I think it should be higher.
 
So far things are looking all right in my boiler. Just fired it back up after a cleaning and inspection.
For some reason I can't get the video to play. Is it avaliable some where else so I could view it?

Logger, what are the last three digits in your serial #
Hi Willyswagon, don't know what video you are referring to. I just posted a picture of the secondary air duct and the damaged area above it. The last three digits of my serial number are 223, and my purchase date was Dec. 2010. The air gate change drawing was dated March 2011. I wish they had told me then as I did not start my unit up until Sept 2011.
 
Burn alot of oak? read this thread https://www.hearth.com/talk/threads/varmebaronen-doesnt-like-oak.47956/
Low return water temperature also can cause firebox condensation which becomes very corrosive.

This video explains how it happens pretty good

I burn some oak, but mostly very well seasoned black locust. My problem started with improper air supply to the secondary burn chamber which caused inefficient burning. Pro-Fab had changed the design but neglected to inform me of the change until it was too late, and the problem had compounded.
 
I just purchased mine in Sept 2012, and my serial is in the mid 400's.
Keep us up to date on this as I'm very interested.
 
I just purchased mine in Sept 2012, and my serial is in the mid 400's.
Keep us up to date on this as I'm very interested.
I'll keep posting as I work though my problem. When you get a chance to check the air duct under the firebrick on the right side, let me know whether you find any blockage and if you find creosote seeping under the firebrick. It you have creosote where the duct is open at the top the oxygen and the creosote is not a good combination.Any blockage of the air duct will affect the secondary burn.Also if you do not see a directive from Pro-Fab shortly on cleaning procedures for this duct, I would contact Ben DeBruyn at [email protected].
 
Thanks, for the info. I have dealt with Ben in the past and found him very honest and easy to deal with.
I wish I would have known about cleaning out this area before I re fired the boiler. Oh well I'll check it next week when I clean it out. Does Ben have the new cleaning procedure, or is the engineer handling that?
Are they thinking all units may need to have these new 1 1/2" holes drilled?
 
Thanks, for the info. I have dealt with Ben in the past and found him very honest and easy to deal with.
I wish I would have known about cleaning out this area before I re fired the boiler. Oh well I'll check it next week when I clean it out. Does Ben have the new cleaning procedure, or is the engineer handling that?
Are they thinking all units may need to have these new 1 1/2" holes drilled?
I agree, Ben has supported me whenever I have called him. When I spoke with him two days ago, it sounded like this was a fairly recent thing that he had done on his boiler. I also don't understand what company policy is regarding changes. They had changed the design of the air gate but never updated me or maybe this could have all been avoided. I never knew where this duct was or of the need to clean it, so it seems there is room for improvement in Pro-Fab's customer support. I would give Ben a call and ask him about it. You can mention you have talked to me.
 
I had no idea about the duct until you showed the picture in this thread. The next time I go into the dealer (hopefully tomorrow) I'm going to pull out the brick and see what a new one looks like so I will know what mine should be like.
If I could get your name so I can mention it to Ben that would be great.
Thanks again for the info.
 
I had no idea about the duct until you showed the picture in this thread. The next time I go into the dealer (hopefully tomorrow) I'm going to pull out the brick and see what a new one looks like so I will know what mine should be like.
If I could get your name so I can mention it to Ben that would be great.
Thanks again for the info.
My name is Mike Koelsch and I live near Canandaigua, NY. Let me know what you find if you get a look at a new boiler. Also see if the dealer has a list of people he's sold the units to and we could get a thread started here for Empyre Elite owners to share info and experiences.I ask some of the dealers in this area as well.
 
My name is Mike Koelsch and I live near Canandaigua, NY. Let me know what you find if you get a look at a new boiler. Also see if the dealer has a list of people he's sold the units to and we could get a thread started here for Empyre Elite owners to share info and experiences.I ask some of the dealers in this area as well.

Maybe there could even be a sticky on the empyre Elite IWB operation. I do not have one, but slowly looking and I like that the empyre have the electrical back-up option for 700$, wich is less expensive than a seperate electric boiler for back up.
 
Maybe there could even be a sticky on the empyre Elite IWB operation. I do not have one, but slowly looking and I like that the empyre have the electrical back-up option for 700$, wich is less expensive than a seperate electric boiler for back up.
Hi Fi-Q, unfamiliar with what a sticky is, let me know. Do you have and Empyre Elite 100 and if so, what when did you purchase it? I believe the electrical backup they offer is only for freeze protection. It will not heat your house.
 
My name is Mike Koelsch and I live near Canandaigua, NY. Let me know what you find if you get a look at a new boiler. Also see if the dealer has a list of people he's sold the units to and we could get a thread started here for Empyre Elite owners to share info and experiences.I ask some of the dealers in this area as well.

See the attached - the first is the new cleanout in the air passage and the second is the new clean out near the door. The .pdf is the cleaning instructions for a V1.
 

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  • E100 V2 Cleanout.JPG
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  • Cleaning-Air-Delivery-Psgs-Elite-100-03-23-2011-jp.pdf
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Maybe there could even be a sticky on the empyre Elite IWB operation. I do not have one, but slowly looking and I like that the empyre have the electrical back-up option for 700$, wich is less expensive than a seperate electric boiler for back up.
Hi again. I did a little research on the electrical issue. Here's what I know. 1000 BTUH = 293 watt hours If you scaled it up to 50000 BTUH you have 14.65 Kilowatts. At 220 volts that would be something like 66 amps. Pretty heavy duty service. Not impossible though.
 
See the attached - the first is the new cleanout in the air passage and the second is the new clean out near the door. The .pdf is the cleaning instructions for a V1.
Thanks so much, can you tell the vintage of the boiler shown in the picture? They have obviously changed this area, but didn't tell me. Earlier in my problem, Ben had sent me the cleaning procedure, but you will notice it does not mention anything about the this lower duct.