I didn't know this: Cat vs non-Cat

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byQ

Minister of Fire
May 12, 2013
529
Idaho
Over the lifetime of the stove a non-cat can match a cat stove in overall efficiency. The cat wears out or gets clogged over time and the wood burner keeps on burning thinking its working fine when in fact it isn't.

"Emissions from both newer non-catalytic and catalytic wood stoves increase over time due to physical degradation of the stoves from use. Within five years the particulate emissions from a catalytic stove may reach the level of an older, uncertified conventional wood stove. According to a report for the US EPA, “over the normal life of the catalyst, the average performance of the heater will be similar to that of a non-catalyst heater that does not change its emission performance as significantly with time.”

I wonder how often the cat should be cleaned and/or changed out?
 
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Cleaned every year. Replaced every 10000 hours.

10,000 hours = ~417 twenty four hour burn days

6 month burning season, 417/180 days = 2.3 years

So change it out every 3 years or less.
 
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Just another government mandate to save the planet. I wonder how the forest fires in California hurt the environment compared to how many stoves are burning without a catalytic converter. Maybe the government should Outlaw wildfires

People like to angrily blame the gummint for the awful tryanny of forcing us to use EPA stoves.

Ever notice that those of us who have been around long enough to use both old stoves and new stoves are never the ones bitching?

That's because the new stoves are flat out better and you couldn't pay us to go back.

I could heat with an old Fisher or even an open fireplace if that's all I had, but I'd be saving up for a modern stove while I did it.
 
People like to angrily blame the gummint for the awful tryanny of forcing us to use EPA stoves.

Ever notice that those of us who have been around long enough to use both old stoves and new stoves are never the ones bitching?

That's because the new stoves are flat out better and you couldn't pay us to go back.
Just be sure to replace your catalytic converter when it wears out in a few years
 
I think he meant cat stoves, not EPA tube stoves. . As far as the govermint, it is just a stepping stone. Restrictions will get increasingly tight until stoves are flat out illegal. Why do you think they use the word "phase".....Phase 1..... phase 2 .......Phase three.....no more stoves.
 
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I bet this is probably true on average. With my progress there is a dramatic difference if the combuster is plugged all the way. But what if it’s 10% plugged? 20% plugged? Would I even notice? Maybe. Would the average user?

I do know I cleaned the cat in a vinegar bath last week and seen a big difference in performance. I probably should have cleaned it sooner.

My neighbor has two Blaze Kings that have burnt the combusters out of them. He won’t replace them. That costs money
 
I think he meant cat stoves, not EPA tube stoves. . As far as the govermint, it is just a stepping stone. Restrictions will get increasingly tight until stoves are flat out illegal. Why do you think they use the word "phase".....Phase 1..... phase 2 .......Phase three.....no more stoves.

You mean "phase".....Phase 1..... phase 2 .......Phase three.....Phase out." Before 'phase out' wood burners will probably have to buy something like a water scrubber machine (not invented yet) to connect to the pipe to make their stoves zero emission.
 
Over the lifetime of the stove a non-cat can match a cat stove in overall efficiency. The cat wears out or gets clogged over time and the wood burner keeps on burning thinking its working fine when in fact it isn't.

"Emissions from both newer non-catalytic and catalytic wood stoves increase over time due to physical degradation of the stoves from use. Within five years the particulate emissions from a catalytic stove may reach the level of an older, uncertified conventional wood stove. According to a report for the US EPA, “over the normal life of the catalyst, the average performance of the heater will be similar to that of a non-catalyst heater that does not change its emission performance as significantly with time.”

I wonder how often the cat should be cleaned and/or changed out?

The original quote (but not byQ) is pretty stupid and makes some pretty stupid assumptions like the user will not replace the cat when it wears out. As the operator of any stove I can do some other pretty stupid things like burning tires or rail road ties that will also cause more pollution. Or I could follow the directions and replace the cat every 10,000 hours. The cats just pop out like a cassette tape and are cheap.
 
I thought cats were kind of expensive - like $300-500.
 
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I thought they were kind of expensive - like $300-500.

Last time I bought one, 1.5 years ago, it was 186$ shipped including the gasket. Woodstock cats are even cheaper as they love to point out! There are some oddball cats that are more expensive but it is your responsibility before you buy a stove model to check the replacement cost of consumable parts.

I have realized a wood savings of over one cord per year since switching from a modern "high efficiency" noncat to a cat stove. That wood savings alone (there are other valuable benefits) pays for a new cat very fast. Easily every year if I'm paying market rate for firewood.
 
Cats aren't that expensive.
 
I'll bet that there are a lot that never change a cat, might even be the majority.

Even more burn wet wood, destroyed the cat in a couple weeks/months and never saw a day where they ever achieved the potential efficiency of the stove.

Same crowd that would burn up or out right remove any insulating blanket or baffle plate from their stove. Then those don't perform as intended either.
 
You mean "phase".....Phase 1..... phase 2 .......Phase three.....Phase out." Before 'phase out' wood burners will probably have to buy something like a water scrubber machine (not invented yet) to connect to the pipe to make their stoves zero emission.

I mentioned wood burning to my next-door neighbor. He made some comment about pollution.

He used to drive a 500-h.p. BMW M6 roadster 2 miles to his office. They now have a Porsche Cayenne S to get to the country club, and his wife drives around by herself in a 3-ton Toyota SUV. :)
 
Just be sure to replace your catalytic converter when it wears out in a few years
If you don't want to replace cats use a noncat stove. There are plenty of them that are compliant. And like said before the new stoves are just better
 
I think he meant cat stoves, not EPA tube stoves. . As far as the govermint, it is just a stepping stone. Restrictions will get increasingly tight until stoves are flat out illegal. Why do you think they use the word "phase".....Phase 1..... phase 2 .......Phase three.....no more stoves.
People say that with absolutely every reglation that comes along. Yet how many examples can you give that have resulted in a ban? I can give you lots where it ended up giving us far better products.
 
The original quote (but not byQ) is pretty stupid and makes some pretty stupid assumptions like the user will not replace the cat when it wears out. As the operator of any stove I can do some other pretty stupid things like burning tires or rail road ties that will also cause more pollution. Or I could follow the directions and replace the cat every 10,000 hours. The cats just pop out like a cassette tape and are cheap.
Do you think the average person keeps up with it? Kinda like changing the oil in your car. Some people change it religiously, some don’t. I have gotten a lot better at that since my car started telling me when to change it.

When I had a small engine repair shop it was appalling to see the condition of most of the equipment that came in. People didn’t do anything until they had a problem.
 
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Do you think the average person keeps up with it? Kinda like changing the oil in your car. Some people change it religiously, some don’t. I have gotten a lot better at that since my car started telling me when to change it.

When I had a small engine repair shop it was appalling to see the condition of most of the equipment that came in. People didn’t do anything until they had a problem.

Wood burners are a very small part of the population and cat stove ownership is rapidly increasing but still a minority among wood burners.

I have only seen two other cat stoves in actual homes in my life and both were well maintained.

I change the oil in my small engines too!
 
Do you think the average person keeps up with it? Kinda like changing the oil in your car. Some people change it religiously, some don’t. I have gotten a lot better at that since my car started telling me when to change it.

When I had a small engine repair shop it was appalling to see the condition of most of the equipment that came in. People didn’t do anything until they had a problem.

Hmm, someone who buys a stove because that's what the salesguy sold them? Probably not.

Someone who buys a specific stove because they did many hours of research and they want the best tool for the job? They are changing it out every 10-15k hours.
 
Wood burners are a very small part of the population and cat stove ownership is rapidly increasing but still a minority among wood burners.

I have only seen two other cat stoves in actual homes in my life and both were well maintained.

I change the oil in my small engines too!
The vast majority of cat stove I see in the feild either have no cat or have one that is doing nothing. Granted most of them are Vermont castings or dutchwests.
 
The vast majority of cat stove I see in the feild either have no cat or have one that is doing nothing. Granted most of them are Vermont castings or dutchwests.
This an interesting thread since I might buy new instead of repairing my Harmon. Are you saying a cat stove can be run with cat removed?
 
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