Drolet Heatmax 2 rust hole

[Gbawol42]

Hey guys,

Anyone have thier Heatmax/tundra rust out on the back air inlet to the firebox? I just took a good look because I swear my furnace was burning a lot hotter than usual and noticed this hole rusted out. (See picture). Also, yes, I did replace that firebrick after seeing it. Now my furnace has been averaging 30-60 degrees hotter flue temp and 50+ degree firebox temp (on my stove thermometer). Burn times have been dropped a little as well obviously with the secondary burn burning hotter.

Contacted Drolet and they said "at this time it isn't an issue. If the furnace is in a humid environment unfortunately like all metals they will rust and the warranty would not apply".

My basement isn't humid and I wasn't too happy with that answer and they haven't answered my reply email.

Just wanted to see what you guys thought and get some input.

 

[brenndatomu]

First I've seen or heard of it...hard to see the hole from the pic...almost looks like creosote scale...but I can see where the hole is, if that's what you say it is...shouldn't be too hard to weld a plate over it though...or even just "glue" one on with furnace cement.
I have heard of several that rusted a hole in the bottom of the center HX tube, at the back between the firebox and the outer air jacket of the furnace (right where the blower is blowing the coolest air on the coolest spot of the whole HX system)
Its funny how some people have issues with this, and some don't...must be a combination of how wet or dry your basement can get, and what minerals may have been in the wood that you burnt to make those ashes...some of the clinkers I get sometimes really make me wonder what was in that tree?!
Do you leave your stove pipe hooked up over the summer? That can be a conduit for some humid air too! I started disconnecting mine and hanging a large desiccant bag in the firebox over the summer...there is usually a quart of water in there by fall...and that's with the inlets and outlet sealed off too!

 

[laynes69]

You positive it's a burn through/corrosion than just creosote? The metal there is fairly thick. I had an original Caddy that was 10 or so years old with no problems. I disconnect my flue pipe and clean everything out at the end of the season, otherwise warm humid air comes down the chimney. To me it looks like creosote scale, is your wood your burning drier?

 

[Gbawol42]

First I've seen or heard of it...hard to see the hole from the pic...almost looks like creosote scale...but I can see where the hole is, if that's what you say it is...shouldn't be too hard to weld a plate over it though...or even just "glue" one on with furnace cement.
I have heard of several that rusted a hole in the bottom of the center HX tube, at the back between the firebox and the outer air jacket of the furnace (right where the blower is blowing the coolest air on the coolest spot of the whole HX system)
Its funny how some people have issues with this, and some don't...must be a combination of how wet or dry your basement can get, and what minerals may have been in the wood that you burnt to make those ashes...some of the clinkers I get sometimes really make me wonder what was in that tree?!
Do you leave your stove pipe hooked up over the summer? That can be a conduit for some humid air too! I started disconnecting mine and hanging a large desiccant bag in the firebox over the summer...there is usually a quart of water in there by fall...and that's with the inlets and outlet sealed off too!

I'll see if I can get a better picture. Stove was still hot and I think I used the flash. Not the best photo.

Good call on disconnecting the pipe for the summer I never thought of that. The dehumidifier keeps the basement humidity down in the summer but I'm not sure about in the firebox itself

 

[laynes69]

I'll see if I can get a better picture. Stove was still hot and I think I used the flash. Not the best photo.

Good call on disconnecting the pipe for the summer I never thought of that. The dehumidifier keeps the basement humidity down in the summer but I'm not sure about in the firebox itself

Do you have central air? If so that would accelerate the corrosion. Since I've put in central air, I've done the best I can do to isolate the cold air from the furnace. Removing the flue pipe and capping things allows the unit to acclimate to the cooler temps.

 

[JRHAWK9]

I think I can see, what looks to be, the outline of the rot. I outlined it with a thin red line.

I have always removed my stove pipe and capped it at both the chimney end and at the stove end at the end of the heating season. Like mentioned above I also put a desiccant bag inside the firebox during the summer months.

 

[sloeffle]

Do you leave your stove pipe hooked up over the summer? That can be a conduit for some humid air too! I started disconnecting mine and hanging a large desiccant bag in the firebox over the summer...there is usually a quart of water in there by fall...and that's with the inlets and outlet sealed off too!

That's a good idea, I never thought about disconnecting pipe. I'll have to do that this year. I do put a bunch of those bags ( they come in packages with metal parts sometimes ) in my furnace at the end of the season that are suppose to help with moisture.

Back to the OP's question, I've been burning my furnace for 12 years now ( same firebox design ) and that area looks as good as it did when I bought the furnace.

Do you leave a 1 - 2" layer of ash in your furnace during the heating season ?

Do you do a good cleaning after the heating season ?

I try to keep as little ash in my furnace as possible. After each load, I rake all of the ash into the clean out and pull all of the coals forwards and reload.

 

[Gbawol42]

I think I can see, what looks to be, the outline of the rot. I outlined it with a thin red line.

View attachment 291681

I have always removed my stove pipe and capped it at both the chimney end and at the stove end at the end of the heating season. Like mentioned above I also put a desiccant bag inside the firebox during the summer months.

Cleaned her up a little and got a better pic. The hole actually might be bigger than I thought. Only the third season on the furnace.

As far as I know I do everything by the book when using the unit. I do leave a layer of ash on the bottom. I have the temp controller controlling the burn. Maybe it did rust out over the summer and I didn't notice? Either way I need to patch it somehow because like I said the furnace is burning hotter now. Actually feels pretty good with the colder temps right now but as we get into spring it will run me out of the house.

 

[Gbawol42]

So it's been a busy summer. Finally got around to really cleaning up and replacing a few firebricks in the heatmax. Then I found out my small rust hole is a lot bigger issue than I thought. I emailed Sbi about it and awaiting their reply. I think I might need a new firebox. Only 3 seasons in it.

If I poked to the left of the air inlet I am sure I would also go through.

Ugh 😫

 

[laynes69]

Jesus! All of the furnaces from SBI over the years never had an issue like this. Did you keep the flue hooked up over the off season? That's some serious rot.

 

[Gbawol42]

Jesus! All of the furnaces from SBI over the years never had an issue like this. Did you keep the flue hooked up over the off season? That's some serious rot.

I did the first season, and after learning I shouldn't had it disconnected the next two. I pretty much burned the stove for 6 months a year, in a dehumidified basement.

 

[laynes69]

A thorough cleaning and a dessicant. I always disconnect my furnace and cap it and cap the flue. I don't need the warm humid air in the basement in the off season. But my heatpump water heater keeps my basement around 50 degrees in the summer. Having air 70 to 80 coming down the chimney is a recipe for disaster.

 

[brenndatomu]

I have been disconnecting the flue over the summer, and hanging desiccant bag inside furnace, but I realized this year that as long as the basement is not super humid, (ours is not...HPWH takes care of that) that just leaving the firebox door cracked open that would make sure inside/outside surface temp matches, no condensation happening that way! (flue still unhooked).
They other thing that people don't realize is how much moisture can be hanging around inside the furnace while a fire is going!
Look at the SBI furnaces that have the HX center tube rot issue, right at the back where the coolest air from the blower blows on it...condensation makes creosote, while the fire is going!
If you think about it for a minute, you load 50 lbs of wood that is 20% MC (that is considered "dry" right?) 10 lbs of that is water...and at 8.34 lbs per gallon, that's almost 1.25 gallons of water you just loaded into the firebox! Sounds like a proper sauna to me...let alone what it would be like with 20% + MC wood!

 

[Gbawol42]

It's making me wonder if I was burning wrong or something. I did not purchase this furnace thinking it would rust out in 3 years.

 

[sloeffle]

I didn't remove my chimney from my furnace during the spring / summer until this year, and the steel on my furnace looks as good as the day I bought it. My furnace is 12 or 13 years old at this point.

I didn't read through all of the previous comments. I'm assuming you do a good cleaning of the furnace in the spring time ?

 

[Gbawol42]

I didn't remove my chimney from my furnace during the spring / summer until this year, and the steel on my furnace looks as good as the day I bought it. My furnace is 12 or 13 years old at this point.

I didn't read through all of the previous comments. I'm assuming you do a good cleaning of the furnace in the spring time ?

Oh yeah, and to be honest besides some ash buildup there really isn't much to clean. The rest of the stove looks great.

The firebricks in the back of the furnace we're really damaged as well, ate away almost. I am not sure what the cause of this was but it seemed to be only in the lower back corner of the firebox.

 

[Gbawol42]

So little update. After going back and forth with Drolet with their warranty process (lots of pictures and questions). They decided it is my fault and will not cover or help in any way. A very disappointing response from them imo. At only 3 seasons old I need to look into another furnace now as I don't trust this one anymore.

They claimed I didn't clean it good enough.

If this kind of rot was possible just because of cleaning I would have cleaned more often. However I never thought of cleaning the back of the firebox anyways, just the heat exchanger and flue.

Not sure if there is still someone who works for Drolet that lurks on here that could help in any way, but I just don't have the money to invest in another furnace, especially at the prices they are currently at.

Thanks guys for all the help I received on here the last 3 years, but even all the tips and tricks that I received and implemened for getting a better burn didn't have me ready for this issue.

 

[brenndatomu]

Yeah that's not very impressive at all!

 

[JRHAWK9]

Hey @SBI_Nick , are ya going to help your customer out here or just sit back and say screw it because you already have his money? Choose wisely, as your next move will show everyone the kind of company you are. The world is watching, as a simple -GOOGLE SEARCH- will bring up this thread for those looking at these products.

Crap happens, nobody is perfect, however it's how one responds to situations like this that separates the good from the bad. Blaming a customer for something completely out of his control is not cool. Please explain to all of us how "cleaning it good enough" would have prevented rusting in an area in which, under normal circumstances, is behind firebrick and ceramic insulation? Can you point out in your owners manual where it states the customer is responsible for removing the firebrick and ceramic insulation to clean behind it in order to prevent rusting? Everyone, including you, know that's compete BS and just an excuse to pass blame. Do the right thing, the world is watching.


tags: Drolet, SBI, Heatmax, rust, Tundra, corrosion

 

[Gbawol42]

Hey @SBI_Nick , are ya going to help your customer out here or just sit back and say screw it because you already have his money? Choose wisely, as your next move will show everyone the kind of company you are. The world is watching, as a simple -GOOGLE SEARCH- will bring up this thread for those looking at these products.

Crap happens, nobody is perfect, however it's how one responds to situations like this that separates the good from the bad. Blaming a customer for something completely out of his control is not cool. Please explain to all of us how "cleaning it good enough" would have prevented rusting in an area in which, under normal circumstances, is behind firebrick and ceramic insulation? Can you point out in your owners manual where it states the customer is responsible for removing the firebrick and ceramic insulation to clean behind it in order to prevent rusting? Everyone, including you, know that's compete BS and just an excuse to pass blame. Do the right thing, the world is watching.


tags: Drolet, SBI, Heatmax, rust, Tundra, corrosion

To be clear this was their response email:

Good afternoon,

We have analysed all the information submitted and the problem is not covered by the manufacturer‘ s warranty.

The manual is quite clear on the maintenance of the furnace. The damage did not occur on a short span of time but over time. Section 9.1.6 in the manual (https://www.drolet.ca/file/45845A_2020-09-04.pdf) about the heat exchangers care says the following:

''Heat exchangers must be cleaned thoroughly at the end of every heating season. During summer, the air in basements is damper and with minimal air circulation within the furnace, it can mix with creosote and/or sooth deposits in the exchangers to form an acid that could accelerate the corrosion process and induce premature decay of the steel.

Corrosion damages are not covered under warranty. Smoke pipe and exchangers must be inspected regularly during the heating season.''

The rest of section 9.1.6 explains what and how to clean the exchangers and combustion chamber. Some people will even disconnect the stove pipe from the furnace and block it off so none of the summer moisture can come into the furnace.

Further in section 9.2.2 under How often should you clean the chimney? the manual says:

''It is not possible to predict how much or how quickly creosote will form in your chimney. It is important, therefore, to check the build-up in your chimney monthly when getting used to the new furnace until you determine the rate of creosote formation. Even if creosote forms slowly in your system, the chimney should be cleaned and inspected at least once each year. (..) CAUTION: IT IS RECOMMENDED TO CLEAN THE HEAT EXCHANGERS, FLUE PIPE AND CHIMNEY THOROUGHLY AT THE END OF THE HEATING SEASON IN ORDER TO PREVENT CORROSION DURING THE SUMMER MONTHS, CAUSED BY ACCUMULATED ASH.''

The manual states very clearly what needs to be cleaned, when and how often it needs doing. Even if he mentioned it earlier on to someone here at SBI about the damages they were already there by that point. The rot is simply worse, and we wouldn't not have been able to repair such damage even earlier on because of the weakness that was already set in the metal from the ash/creosote and ash chemical reaction.

We do not recommend the unit to be repaired.


Best regards,




Elizete Cardoso Ibrahim
Service après-vente/Réclamations
After sales service/Claims

I responded by saying that I cleaned the heat exchangers and flue regularly, and I wasn't sure what that had to do with the back of the firebox. That response was 2 weeks ago and I haven't got a reply.

 

[brenndatomu]

Yeah that is certainly not part of the HX...and even if you are the oddball that cleans your furnace to the point of taking all the firebrick out, there is a still a layer of ceramic insulation behind them...and every one I have ever messed with is stuck to the metal...the insulation they use on the Tundra/Heatmax is pretty thin, and there is no way its coming off without destroying it (BTDT)
That does NOT sound like reasonable maintenance expectations to me!

 

[JRHAWK9]

Yeah that is certainly not part of the HX...and even if you are the oddball that cleans your furnace to the point of taking all the firebrick out, there is a still a layer of ceramic insulation behind them...and everyone I have ever messed with is stuck to the metal...the insulation they use on the Tundra/Heatmax is pretty thin, and there is no way its coming off without destroying it (BTDT)
That does NOT sound like reasonable maintenance expectations to me!

I agree. It was them verbally trying to:

 

[Gbawol42]

Yeah that is certainly not part of the HX...and even if you are the oddball that cleans your furnace to the point of taking all the firebrick out, there is a still a layer of ceramic insulation behind them...and every one I have ever messed with is stuck to the metal...the insulation they use on the Tundra/Heatmax is pretty thin, and there is no way its coming off without destroying it (BTDT)
That does NOT sound like reasonable maintenance expectations to me!

Well we will see if this gets me anywhere. I contacted them directly before blasting them on here, and it didn't get me anywhere.

Ball is in their court I suppose.

 

[woodey]

I heard that there was a furnace manufacturer that has a 25 year warranty on firebox and HX.

 

[Highbeam]

There are bagillions of these furnaces out there and we aren’t seeing this problem regularly so it could be a defect or something unique about this installation. SBI should be more helpful but I wouldn’t expect them to just send a replacement that might suffer the same fate.