Austroflamm Integra cast iron too thin?

[LuvMyStove]

Last year I posted a plea for help when our 1994 Integra started sooting up the glass and the flames kept getting smaller and darker orange and the heat output diminished. The stove couldn't even make it 24 hours before I had to shut it down and clean it again to get any decent heat. I even took out the cast iron, cleaned out the smoke chamber and exhaust fan housing, etc.) and stove pipe. After trying about a dozen other "cures" (electrical, air flow, etc.). I finally took the cast iron out again and replaced the gasket behind the bottom panel. Success! White flames and more heat than ever. I don't know why that worked except that maybe the gasket had gotten thin and air was coming in around the edges of it and into the burn chamber. How that would cause the flames to die down and blacken the glass, I don't know. Anyway I replaced the gasket in October and everything was fine until a week ago when it started giving us the same problems. Weak orange flame, blackened glass, no heat. Yesterday I replaced the gasket behind the cast iron again and the stove is running great. At $36 a pop for the gasket, I don't want to be replacing it every 4 months. We're wondering if, after 20+ years, the cast iron wall has gotten thin and needs to be replaced. If so, I have two questions:
1) Does the top cast iron section (which doesn't have a gasket) also have to be replaced?
2) What is the best company to buy the cast iron from? Most prices I've seen are around $300 for each section, which is why we'd prefer to just replace the bottom. Thanks.

 

[Mark_ms]

I don't know if the walls get thinner, but I suppose it is possible over the last twenty years of use
I think that if you had to replace both walls at the same time they would price them accordingly.
Four months of use would be almost a full season of burning and your going replace most gaskets at the end of season anyway.
flamman posted this link a while back for wall gasket in bulk.

 

[skibumm100]

The cast iron will not get thin....it doesn't wear and really doesn't corrode. You'll be wasting your time (and money) replacing it. Just think of how many gasket (and pellets) you can buy for the cost of that plate. How often do you take the cast plates out to clean back there? I pull the plates and clean out behind them every week. The stove burns much better after it's cleaned back there. I just cleaned the stove and pulled the plates during half time. That way I could listen to the vacuum cleaner instead of Katy Perry. ;-) There are little cut-outs behind the tubes at the bottom. Those hole must be kept clean and unblocked by ash. That is where 100% of the combustion air goes that passes through the stove. It those holes start to get blocked you will have poor performance (poor combustion, orange flames, dirty glass, poor heat). Guess where the ash goes when you move the cleaning rods up and down?......most of it falls to the bottom behind the bottom plate.

Also, double check to make sure your door latch is adjusted correctly and the door gaskets fit tight (dollar bill test).

I'm not sure why replacing the insulating gasket would cause too much of a difference for you unless that's the only time it gets cleaned back there. I think there have been people that run the stove without the panel gasket. I bought a sheet of Lytherm from McMaster-Carr. Here's a link to it... http://www.mcmaster.com/#93285K18 I think it's purpose is to keep the heat from short circuiting the heat exchanger tubes, but I'm not positive.

The only reason to replace the cast iron plate is if you drop it and break it.

FWIW, when I got my stove it wouldn't run. The guy who owned it before me couldn't get it to stay running. Glass was dirty (I mean completely black), lazy orange flame. I figures it had something wrong with it. The only problem with the stove is that it was never completely cleaned out. Once cleaned out, it has run like a top.

Good luck and let us know how it turns out.

 

[Bioburner]

Another stove design that plugs itself and needs lots of TLC to run properly? They still seem to make stoves with the same issues today or worse. One of the imports controls the flame by running air through the burn chamber instead of controlling the exhaust fan speeding up the air around the exchangers and out the exhaust

 

[skibumm100]

I guess?? I don't consider 20 minutes a week "a lot" of TLC. I do wish there was a big ash drawer instead of the shallow pan around the burn pot. If it had one, though, it wouldn't hold almost 100# of pellets in a short insert that would fit in my small fireplace.....trade-off's. I guess I'll keep the longer run time and a quick 2 minute vac job every couple days. I think the Accentra would hold about 58# in the same space envelope. Of course it costs 8X as much as I paid for my Integra ($500, well used). That's 3+ years of pellets. Nice stove, just out of my price range.

 

[Bioburner]

Balance of,do I want to clean a bit more and fill less, do I get a older stove cheap and deal with the quirks that all stoves have.
I have a family member that wants a insert to shove into the old fireplace and I'velots to consider. Two nice Harmans on CL for $1700 or a older Whitfield for $500. How much work do they(me) to do daily , weekly etc

 

[skibumm100]

Balance of,do I want to clean a bit more and fill less, do I get a older stove cheap and deal with the quirks that all stoves have.
I have a family member that wants a insert to shove into the old fireplace and I'velots to consider. Two nice Harmans on CL for $1700 or a older Whitfield for $500. How much work do they(me) to do daily , weekly etc

Accentra's or 35i's? I only saw one Accentra for $1500 on CL and when I called it was gone. It lasted 45 minutes.... This was a couple years ago when I first did my install. I had been looking for an Accentra insert for quite a while and the best prices were $2500-2800 bux, used. Too much money for a used stove. I would just buy new at that point but the ROI didn't make sense. Too many years to pay back. I bought a used York to get in the game and replaced it with the Austro the next year. I paid a little over $1600 for the York and $500 for the Austro so my ROI is getting better. If I ever get my St Croix Revolution installed, it will get worse. I think I only have a total of $450 into that one but I have to do a lot of labor to get that one in. New flue and ductwork, also, so that will drive the ROI up. I burn pellets to save money.

 

[Bioburner]

Both Harmans are 52i.We don't mess around with little stuff much around here in the north central. Another term, go big or go cold is applied around here a lot.

 

[skibumm100]

That's a great price for a 52i. I don't think you would find them that cheap around here. Low(er) oil prices and high pellet prices with less availability may translate into some good used deals come spring.

 

[Bioburner]

Oil prices jumping and strikes by steel workers at 9 refineries Sunday might put the heating fuel prices on a rocket ride back up. Gas prices went up 15 cents since last Friday. That's a 7 % hike for the first weekend of February. Might be no deals on non conventional heating sources by spring

 

[Flammam]

The white gasket behind the lower cast wall prevents air leaks between burn chamber and the heat exchanger area. I pull my lower and upper cast wall every ton or about once every 4-5 weeks and deep clean that area back there.Its very important to clean behind the heat exchanger tubes where the rectangular tubes. My stove story is about the same as skiibum got my stove for free after my SIL couldn't keep it running after the first year. Ya it was clogged solid with ash. I would say I have about 80 tons through this stove since I got it.

 

[Mt Bob]

Sorry have not been here for a while.The lower gasket is very important,it promotes good airflow that gives good heat and also keeps the little rectagular channels[holes open behind the heat exchanger tubes.If the lower wall warps it can also change the airflow to affect this.The upper cast can be used untill it warps so much it cannot be bolted back in.Usually about 6-10 years for both,a very well built forgiving unit.Pulling the combustion blower and the right cleanout cover is highly reccomended if you do not have the use of a high pressure air system,even the LBT will not clean it.When kept clean the old integra is as efficent as most of the new stoves.

 

[skibumm100]

Sorry have not been here for a while.The lower gasket is very important,it promotes good airflow that gives good heat and also keeps the little rectagular channels[holes open behind the heat exchanger tubes.If the lower wall warps it can also change the airflow to affect this.The upper cast can be used untill it warps so much it cannot be bolted back in.Usually about 6-10 years for both,a very well built forgiving unit.Pulling the combustion blower and the right cleanout cover is highly reccomended if you do not have the use of a high pressure air system,even the LBT will not clean it.When kept clean the old integra is as efficent as most of the new stoves.

So I assume the lower gasket should cover the entire cast plate? I have been cutting it to fit into the recess and just be an insulator. Could you just use the flat gasket like what is used on the glass around the perimeter of the plate? I'll check my lower plate with a straight edge to see how flat it is.

 

[Mt Bob]

Yes,yes, no and yes.(might not be in right order.Gasket does not "seal" the lower plate,fits in the "recess".Over the years I have run--broken gaskets,gasket just around the edge(and opening around auger drop) and no gasket.I believe the key is the insulation(blocking heat) factor is the key,otherwise can end up with an airflow restriction because of high heat at the bottom of the heat exchanger tubes.The fan can only do so much.Sealing around the drop tube is also very important because can draw heat straight in to tube area(think warped plate).I experienced running no gasket poor heat output and warped plate.Used silicone to seal around drop tube for 2 years untill the plates were made/imported again,worked great.As said before,the 4 small rectangular holes behind the heat exchanger tubes is one of the most important things to keep open.Also pulling the cover plate on right side and clean across is important,unless you can blow out with compressed air.The upper and lower plate warp with time,just file holes out a little to install easier.When center of upper plate gets close to front edge of stove,grind off a little to improve airflow.My upper is still original,but not very straight!

 

[Mt Bob]

Also when bearings in exhaust blower start to drag,can cause problems,but easily replaced.You should not have to pull the interior plates and clean untill after 1 ton(unless other issues-flue,etc) but will realize more heat if done more often.As far as output,as this winter I am running an accentra upstairs and only used old unit 3 times,the accentra fs is way faster to clean,almost as quiet,but not as efficient as the old unit down in basement.The integra,running on 2/3 you could not stand within 3 ft of the front because of the heat.The acc. on high you can stand within 15 inches,BUT can clean it in one beer,starts and stops itself,and pellet quality not an issue because of exhaust probe.Duayne designed this unit to be very user friendly,and I like it.

 

[skibumm100]

Bob,

Thanks for the details on the Integra. Since I got mine used and dirty and I could never see buying the factory "gasket"/insulator for the price they get, I never had seen the correct one to measure it. IIRC, I cut mine to 9" X 24". I cut them five at a time and replace every couple months or when they fall apart. I make them out of 1/8" thick ceramic insulation. Is 1/8" the correct thickness, or is the factory one 1/4".

 

[Flammam]

I use the material that skibum uses and just cut my own. The material is 1/8 thick, which is the same thickness as stock

 

[LuvMyStove]

The cast iron will not get thin....it doesn't wear and really doesn't corrode. You'll be wasting your time (and money) replacing it. Just think of how many gasket (and pellets) you can buy for the cost of that plate. How often do you take the cast plates out to clean back there? I pull the plates and clean out behind them every week. The stove burns much better after it's cleaned back there. I just cleaned the stove and pulled the plates during half time. That way I could listen to the vacuum cleaner instead of Katy Perry. ;-) There are little cut-outs behind the tubes at the bottom. Those hole must be kept clean and unblocked by ash. That is where 100% of the combustion air goes that passes through the stove. It those holes start to get blocked you will have poor performance (poor combustion, orange flames, dirty glass, poor heat). Guess where the ash goes when you move the cleaning rods up and down?......most of it falls to the bottom behind the bottom plate.

Also, double check to make sure your door latch is adjusted correctly and the door gaskets fit tight (dollar bill test).

I'm not sure why replacing the insulating gasket would cause too much of a difference for you unless that's the only time it gets cleaned back there. I think there have been people that run the stove without the panel gasket. I bought a sheet of Lytherm from McMaster-Carr. Here's a link to it... http://www.mcmaster.com/#93285K18 I think it's purpose is to keep the heat from short circuiting the heat exchanger tubes, but I'm not positive.

The only reason to replace the cast iron plate is if you drop it and break it.

FWIW, when I got my stove it wouldn't run. The guy who owned it before me couldn't get it to stay running. Glass was dirty (I mean completely black), lazy orange flame. I figures it had something wrong with it. The only problem with the stove is that it was never completely cleaned out. Once cleaned out, it has run like a top.

Good luck and let us know how it turns out.

Thanks for your informative response and special thanks for saving us $300+ on the cast iron. I will start cleaning the stove more regularly (behind the cast iron). I clean the burn chamber/pot every day. I used to be able to clean behind the cast iron twice a season ("season" = 7-8 months). The past couple years I had to increase the frequency to about every six weeks and now even more often. I definitely think the rapid increase in soot production (right now it's overnight) is due to an air leak into the chamber - either around the cast iron or around the door seal. Two weeks ago I took out the cast iron and cleaned thoroughly, also the smoke chamber behind the tubes and the four square holes behind the tubes. I replaced both the cast iron gasket and the rope gasket on the door. The stove ran like a champ for about a week - white flame, no soot, incredible heat output on setting 2 of 6 (using the notches around the dial as a gauge). Then every day the flame got weaker and sootier. What confuses me is that I never had to do it that often. The need for cleaning behind the cast iron just keeps increasing expodentially (sp?).
Now I want to troubleshoot two things if you'll help. First, the door. What is the dollar bill test? I assume that you shut a bill in the door and see if you can pull it out? If yes, how do you adjust the door to tighten it? I assume you adjust the latch and not the hinges. The soot does seem to be building in from the edges of the glass, but I don't know if that means the air is coming in past the rope gasket, or from inside the chamber (past the cast iron gasket). If I can't pull out the dollar bill, does that mean the rope gasket is probably tight enough? Let's start w/ that and then move back to the cast iron gasket as the culprit. Thank you very much again.

 

[Mark_ms]

The dollar bill test is as you described. If it comes out loosely the gasket needs to be replaced and the door needs to be adjusted after gasket is installed.
To adjust the door is a combination of hinge and latch adjustments.
On your glass you should have a gasket on 3 sides of the glass sides and bottom. leaving the top of window without gasket is part of the airwash system.
When you have both cast iron walls removed look at the top (inside) you probably have build up in that area, a combination of vaccumming and scraping will remove this.

 

[LuvMyStove]

The dollar bill test is as you described. If it comes out loosely the gasket needs to be replaced and the door needs to be adjusted after gasket is installed.
To adjust the door is a combination of hinge and latch adjustments.
On your glass you should have a gasket on 3 sides of the glass sides and bottom. leaving the top of window without gasket is part of the airwash system.
When you have both cast iron walls removed look at the top (inside) you probably have build up in that area, a combination of vaccumming and scraping will remove this.

Thank you again. If I cannot pull the dollar out, the door seal is tight enough? Or should it just pull out with some degree of resistance? Your mentioning the airwash system reminded me that I haven't cleaned that out in some time. I used to use an old credit card but if there's a buildup in there I'm not sure that would be rigid enough to dislodge the buildup. In any case, I'll try to clean that out when I shut the stove down tomorrow. I do clean out the top of the stove when I take the cast iron out. I use a paint brush to knock down the loose stuff and then a steel rod to take down the buildup. What I don't understand is what happens to the hot air from the flames when it rises to the top of the stove. Does it go over top of the cast iron and then down the backside of it where the tubes are, and from there through the square holes to the exhaust chamber? I'm probably not phrasing the question right, but if you can understand it maybe you can educate me. Thanks.

 

[Flammam]

Thank you again. If I cannot pull the dollar out, the door seal is tight enough? Or should it just pull out with some degree of resistance? Your mentioning the airwash system reminded me that I haven't cleaned that out in some time. I used to use an old credit card but if there's a buildup in there I'm not sure that would be rigid enough to dislodge the buildup. In any case, I'll try to clean that out when I shut the stove down tomorrow. I do clean out the top of the stove when I take the cast iron out. I use a paint brush to knock down the loose stuff and then a steel rod to take down the buildup. What I don't understand is what happens to the hot air from the flames when it rises to the top of the stove. Does it go over top of the cast iron and then down the backside of it where the tubes are, and from there through the square holes to the exhaust chamber? I'm probably not phrasing the question right, but if you can understand it maybe you can educate me. Thanks.

Yes the exhaust path is up over the top and down behind the cast iron plates past the heat exchanger tubes through the rectangular hole to the combustion blower and flue.

 

[skibumm100]

Thank you again. If I cannot pull the dollar out, the door seal is tight enough? Or should it just pull out with some degree of resistance? Your mentioning the airwash system reminded me that I haven't cleaned that out in some time. I used to use an old credit card but if there's a buildup in there I'm not sure that would be rigid enough to dislodge the buildup. In any case, I'll try to clean that out when I shut the stove down tomorrow. I do clean out the top of the stove when I take the cast iron out. I use a paint brush to knock down the loose stuff and then a steel rod to take down the buildup. What I don't understand is what happens to the hot air from the flames when it rises to the top of the stove. Does it go over top of the cast iron and then down the backside of it where the tubes are, and from there through the square holes to the exhaust chamber? I'm probably not phrasing the question right, but if you can understand it maybe you can educate me. Thanks.

Sorry, I haven't been checking in too much lately. Mark and Flammam answered in my absence. Thanks guys!

When you close the door on the dollar bill, you should not be able to pull it out. I go around the whole perimeter of the door seal when I check mine. If the door gasket is the correct size, and the door latch is adjusted correctly, it should be tight all the way around. You shouldn't really get much build up in the airwash area. The fresh air goes in there so ash shouldn't get into that area. As Bob stated above, the "gasket" behind the lower cast wall isn't really for sealing. It's not a gasket, per se, it's insulation.

FWIW, it's been a week since I cleaned the stove. I'm using Douglas Fir pellets but it still gets dirty. I even have been having clinkers after burning for a day. I've just been popping them out and scraping the pot. I expect there is a fair amount of ash under the pot. Tomorrow I'll pull it apart and give it a good cleaning. Should be good for another week.

 

[skibumm100]

Wow! What a difference a clean stove makes. I pulled the plates out and brushed off the HX tubeswith a paint brush and vac'd out all of the ash. My flue gas temp was 280 deg F and convection blower outlet was 124 deg F before I cleaned it. It has a lot of ash under the burn pot from scraping the pot and it had a pretty good clinker this morning. I think the ash blocks the holes in the bottom of the pot. After a good cleaning, my flue gas temp dropped to 245 deg F and the convection blower outlet was 150 deg F. This is on a lower setting, so less fuel going in. There is quite a bit of space between the tube scrapers and the HX tubes. I would like to fix that someday. I would expect all of our tube scrapers in the stoves are in similar condition, given the age of the stoves.