Why catalytic converter?

[polaris]

I have never owned one but are there real advantages? I was talking about this with a friend and he thought that "they are a thing of the past". When compared to other EPA stoves equipped with reburners do they offer a better fire view? A cleaner burn? Less expensive? I thought several manufacturers were still producing them if so who are they?
Thanks
Joe

 

[Risser09]

A catalytic converter burns wood smoke at a lower temperature than it would normally require without it. Therefore, you can extend the burn time of your wood just by "smoldering" the fire with the built in damper on the stove. This will ultimately lead to less rapid disintegration of the wood, with the energy (BTUs) being used at a slower pace. They require a 500º temp to begin ignition of the smoke. A clean burn is achieved because those smoke particulates are burnt off, instead of being released into the atmosphere. The cat for my stove costs $125 and should last 5-6 years. I bought a Woodstock Keystone stove.

 

[Adios Pantalones]

Ya, from what I read- you can get a better burn time. This is great for someone with a smaller space to heat- you can heat it for a longer time without burning yourself out of the room with a bigger firebox

 

[polaris]

Thanks. If you use it without the cat( as in replacement no longer available) is it simply a pre EPA type stove as in straight up and out?

 

[pinewoodburner]

Thanks. If you use it without the cat( as in replacement no longer available) is it simply a pre EPA type stove as in straight up and out?

There are several aftermarket companies that make them. If the cat is a standard size, the replacement is not much $. Replaceing the cat is cheeper than replaceing the air tubes. The cat on my Woodstock Fireview can be replace in 10 minutes. Before purchasing, I looked at Hearthstone stoves, non-cat, vs the Woodstock stoves, cat stoves. Both are soapstone but the cat stove has longer burn times and put out less polutants. I was looking for the long burn times. Both Hearthstone and Woodstock make great soapstone stoves. You can not burn trash in a cat stove.

 

[VTSR5]

Thanks. If you use it without the cat( as in replacement no longer available) is it simply a pre EPA type stove as in straight up and out?

In the case of my WinterWarm (small) catalytic insert, it can be burned with the by-pass damper open in "up-draft mode". This is how the stove is meant to be warmed up and operated until the cat is engaged. In fact, it burns very cleanly this way with no smoke once it's really rolling (but it needs lots of air to burn clean, and the fuel wont last long in updraft mode, so not practical). If your question is, can you run the stove without the combustor installed, I think the answer is, yes, stove will work and produce heat, but not efficiently, and it is not legal, so Al Gore will fly his private jet to your home and beat you with a rolled-up recycled newpaper.

I'm amazed at what my small insert, with it's puny 1.25 cubic foot firebox, can do. And I'm pretty sure it's due to the fact its a catalytic design. I'm still learning with the thing, but I'm now regularly getting 8 to 10 hour burns with plenty of active coals left. Or it can be burned hotly at max output for about 4 hours. That's pretty good flexibility for a stove I can only fit four splits into.

Lower average firebox temperature is the key to why catalytics can acheive longer burn times. The combustor needs initial firebox temps above 500* to properly engage. After that, however, the cat reaction is self-sustaining. So that means firebox temps can fall below 500* without extinguising the cat, so long as sufficient fuel (smoke) and air are present. This is why you can dial the heat down on a catalytic model and get a longer burn.

Non-cats need higher firebox temps for a longer period of time. That typically means converting fuel to heat faster.

The simplicity of non-catalytic stoves has a lot of appeal to me. But having experienced a catalytic stove now, I find them complicated but very interesting, flexible and useful for the way I want to burn. I really do need good overnight 8 hour burns, and good work-day or ski-day burns as well. So I would not hesitate to buy another catalytic stove after doing my homework on the brand and model in question.

 

[Risser09]

I think the longer burn time is a definite advantage. Last night I put in 4 splits and woke up to 1 log still burning with a stove temp of 250. From there it only took a few more splits to reload, ignite, wait 15 mins for the initial warming, and turning the cat on for the rest of the day. It's pretty much nonsense free, aside from cleaning the cat every month.