Life span of a catalytic combustor in hours

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Jerome P

New Member
Jan 20, 2023
31
West Central Wisconsin USA
I'm just curious in knowing how many hours a catalytic combustor last if running the wood stove as primary heat, 24/7 hours for 8 months in average 20 F daytime & 10 F night time in Wisconsin, burning dry red oak @<20% moisture content, burn no garbage materials except some non glossy paper, minimum air temp shock to combustor while opening the loading door, a couple of over firing couple times a year and proper maintenance on them.

70's ranch style house with decent insulation, 1100 sq ft upstairs, 1100 sq ft in uninsulated basement which the stove will be, a couple drafty windows, I like the upstairs temp at 76 degrees.

I'm asking so I'll know how many combustors & combustor gaskets to have on hand now since prices will only continue to go up. I would like to order these from Midwest Hearth. My stove & chimney install won't happen for a couple of months.
 
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10000 to 15000 hours
 
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24 X 7 X 4.3 = 722.4 hrs a month. x 8 = 5779.2 hours over the 8 month span. Based on Bholler's post that is 2 to 3 years.
My insert has a 10 year warranty on its combustor, but I doubt I will be burning 24/7 for 8 months in central CT
 
24 X 7 X 4.3 = 722.4 hrs a month. x 8 = 5779.2 hours over the 8 month span. Based on Bholler's post that is 2 to 3 years.
My insert has a 10 year warranty on its combustor, but I doubt I will be burning 24/7 for 8 months in central CT
All cats are warrantied for 10 years atleast. Which only means that your first one will be free
 
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All cats are warrantied for 10 years atleast. Which only means that your first one will be free
True, I'm not sure what its stipulations would be.
 
True, I'm not sure what its stipulations would be.
There really aren't many when your first one wears out they will replace it. After that it's on you
 
There really aren't many when your first one wears out they will replace it. After that it's on you
Sounds good, thanks.
 
2 to 3 years is typical of what most here report
 
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2 to 3 years is typical of what most here report
I wonder if others stock up on cat combustors. Planning to run this new BK when installed, for the next 15-20 years or until my last day, which ever comes first. Lol
 
I wonder if others stock up on cat combustors. Planning to run this new BK when installed, for the next 15-20 years or until my last day, which ever comes first. Lol
I don't
 
I might get a couple extra this year @$260 apiece. There is one with the stove and more than likely that replacement from the warranty.
 
I replaced mine after 6 years of burning. I dont burn 24/7 for 10 months so mine last longer. Put the new one in and it seems to burn the same as the last. So I keep the old as a back up and will just vinegar bath it once this one goes and use it till I get a new one.
 
I wonder if others stock up on cat combustors. Planning to run this new BK when installed, for the next 15-20 years or until my last day, which ever comes first. Lol
It depends on the stove and the supply line. It's a bummer to have a cat peter out and no replacement during a bad cold snap or extended power outage. Sometimes the shortage can last for months. I would always have a spare with gasket on hand.
 
All cats are warrantied for 10 years atleast. Which only means that your first one will be free
This varies with the stove manufacturer. It looks like Hearthstone pro-rates the replacement after 2 yrs and after 6 it's on your nickel. Third-party replacement cats don't have this warranty.
 
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Agree with everyone here. Most of what I have seen is 10-15k hours which on avg will be about 2-3 years. Some have spare parts some don’t. With that said I advocate for a spare gasket and cat. You never know when you’ll need it, and with todays economy and supply problems you never know for sure anymore when and if you can get it, and they aren’t like gallon of milk that will expire if left sitting for a month.
 
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10 Years 120 Months 3,652 Days 87,648 Hours 5,258,880 Minutes 315,532,800 Seconds
 
Good FAQ on combustors: https://midwesthearth.com/pages/catalytic-combustor-faq

I would keep one on hand with a gasket, doesn't hurt and I have never seen anyone say anything about an Expire date on cats sitting on the shelf in a box.
Good reading, thanks!

Hard to believe I've been breathing in all those chemicals in that smoke every time I fire up the OWB last 22 years.🤢 Can't wait until I make the switch and heat with the Blaze King.
 
10 Years 120 Months 3,652 Days 87,648 Hours 5,258,880 Minutes 315,532,800 Seconds
They absolutely will not last that long in use. I know you are probably joking just making sure there is no one who takes that seriously
 
I've run 3 King's over 27 years. My combustors have provided excellent performance in 2 of the King's for 8 years each, now have KE 40 on 3rd winter heating.

This topic has come up many times. The vast majority of owners of our stoves receive somewhere between 8-10 years.

They are NOT as good in year 10 as in year 1, no question. But not all cat stove designs are equal. Some use vertical integration, no flame shield, non adjustable front doors (keep air leaks to a minimum), some without bypasses, some without rear combustor baffles, some with a method to protect from excessive temps during considerable stack effect, etc, etc.

If you are tuned into your stove, your ability to "sense" a decrease in efficacy is more likely. Go out, look up. If you see sustained smoke other than after reloads or cold starts, you could be nearing the end of combustor efficacy.
 
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Also be warned of a misleading tactic of presenting expected cat life in years. That's ridiculous. Some people burn 500 hours per year and some people burn 5000 hours per year. Still others don't even care if their stove smokes so they will run with a dead cat and count those years. You have to be careful to not be misled when asking questions about cat life, often the offenders don't even realize what they're doing. The huge majority of wood burners are not 24/7 heaters.

I only expect 10,000 hours of cat life in my stove running softwoods on low. Any more is a bonus but I've also logged hours and life of each of the last 5 cats and have consistently only gotten a bit more than 10,000 before the smoke gets too bad and the tar starts dripping off of my chimney cap. For the sake of planning, you should plan on 10,000. Bonus if it lasts longer. Oh, and that 10,000 hours will take you 100 years if you only burn 100 hours per year. See how that works?!

I've never had a problem getting new cats cheaply and quickly from amazon but I've seen other brands have supply problems and with the whole corona fiasco I went ahead and bought a backup fresh cat. I will replace the backup when I cycle it in here soon. New cats come with the gasket installed so it's all ready to go. I like that.

I've become a part time burner so I expect more than 2 years from future cats, maybe 6 or 7 like the other part time burners get. Another wild card is the OP burning hardwoods at higher output levels might allow the cat to live longer since it isn't working as hard as my stove on low burning resonous softwoods.

Finally, even at 10,000 hours these cats are a bargain. The cat system allows me to burn wood so much more efficiently that the cat pays for itself twice over in wood savings. I burned and still burn a lot of wood in a modern noncat and a lot of that wood is wasted up the stack because these noncats depend on high combustion temperatures to burn the smoke.
 
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@BKVP I only ask this because I have never seen it asked before, but what is the shelf life (never installed) of an OEM BK cat?
Never damaged, decades.