Cat / Non Cat

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Not having owned or operated a cat stove from other's descriptions it sounds like you have a by-pass valve to switch over when the stove reaches X temp . . . other than that it sounds like the controls are pretty much the same and pretty basic -- just a lever or similar mechanism for air flow. In terms of operating controls, I think both are pretty simple and basic.
 
okay, here is the real problem. I am looking to purchase a wood stove (never have had one). I have done some reading on the Harmon Oakwood, VC and Jotul there seems to be some problems with there evenburn systems. So, I want the safest stove that I can get Cat or Non Cat . Please keep in mind that I have not used a stove before.

I will be heating a 2000 SF home Tri-level. The stove will have to go on the middle floor.
 
I prefer a non-cat!

Simpler, and may be equally clean or more.
 
I keep reading about overfire on non cat stoves. Is this something to be concerened about. All stove dealers around here say pellet stoves but, the cost of pellets keep climbing (310.00 a ton).
 
I burned a non-cat VC Encore last winter. For a variety of reasons I would not consider it to be 'easy' to control. It doesn't really have a lot to do with the physical levers on the stove so much as being able to know exactly what needs to be where when. My experience there, however, has far more to do with the 'everburn' style of technology I believe than the whole cat/non-cat debate. I highly recommend you read up on whatever stoves you consider before you buy (search the forums for that particular stove!)
 
Cats have more control because the air can be shut down more, non cats have a seperate secondary air inlet that cannot be shut off unless you modify, but then you risk creosote build up. Some cat stoves like Blaze King also have a auto thermostat that will control the air even more.
 
Thanks, I see what you are saying. I am looking for a stove that can burn at night while I am in bed. I see your a newbie do you feel confortabale burning at night? I just do not want to purchase a stove and not be able to let it burn with out me watching it all the time. I heard read on several stoves that are hard to control is this all the time or untill the evenburn kicks in.

Thanks,
 
Two different things that you're asking. First off, eliminate the VC from your list, they are a lame duck. Even the VC cat stoves which are notoriously hard to operate.

1) Easiest to operate: The non-cat by far. Almost all non-cat stoves have a single air control lever. Hot one way and colder the other. The cat stoves have a bypass lever which must be operated at a particular moment in addition to the single air lever. Both stoves are easy to operate by the stove enthusiast but I would have a hard time teaching my wife when to engage the catalyst on a cat stove.

2) Most controllable: The cat stoves. This is because the non-cats have a minimum air setting that prevents the operator from shutting them down too far and smoldering the fire and producing pollution. The cat stoves can be operated at low heat levels for long burns or high heat levels for short burns. The cat is superior because of this.

You don't need to worry about sleeping or going to work. Both stove types are made to be loaded and left alone for the entire burn period. I completely close down the air control on my non-cat and go to bed. You can test this method during the day to gain confidence.
 
PART 1

Hopefully we can put aside some of your fears here. I grew up with wood heat all my life (I'm 32 now), but I never truly "operated" a wood stove until last year. We purchased a Lopi Endeavor (non-catalytic) in November of 2008. And even though I had never operated a wood burning appliance in all my adult life, the stove was easy to learn and operate. But let me make this one thing absolutely clear before I go any further: NO stove will operate easily or properly UNLESS you have dry, seasoned wood. This is wood that has been cut, split, and stacked to dry for at least a year. Not "seasoned" as in "it was laying on the ground as log for 6 months in the rain before the guy selling it bucked it up and split it last week".

A final point before going on. Today's EPA certified stoves are made to burn in cycles: you start a fresh fire, establish a coal bed, and then load larger splits. Once that load is fully engaged and "charred," you start reducing the amount of primary combustion air you give the wood. This causes the secondary combustion (the burning of the smoke and gases released by the wood) to take over as the wood basically lies there and "bakes" while its gases and smoke combust and burn. The wood then enters the charcoaling stage, which produces a small blue flame rising whispily just above the coal bed. Learning to operate your stove around this burn cycle will improve performance and your own comfort level and confidence level.

Now, with those points made, let's move on. Operating a non-catalytic stove is relatively easy. Most have a single control on the front of the stove that allows you to control what is called the "primary air". All new EPA certified stoves have two forms of air intake: primary air for ignition of a fresh load and secondary air for secondary combustion. Unless you modify the stove, there is really no way to control the secondary combustion air - it is simply a design element of the stove. The secondary air is usually pulled into the back of the stove and travels up the firebox inside the stove and is "injected" onto the top of the fire via burn tubes with holes drilled into them. This allows the gases and smoke produced by the primary combustion to ignite and burn. You get 1.) more heat per load and 2.) much cleaner burns because of this secondary air. So all you really have to worry about "controlling" in the primary air.
 
I'll not beat around the bush:

Although I did learn how to burn in the VC and did in fact burn at night, in the end I was not comfortable with the stove. Mostly due to the fact that my wife was not willing to learn how to do it. Yes, the mechanics were simple, but there is an art to knowing when to engage the bypass and if done too early you will not get it to engage (smoke etc) too late and you may overfire rather quickly. So, after a few mistakes there my wife decided she just would not bother feeding the stove unless it was an easy feed - i.e. a full bed of coals she could just top off and walk away from. So totally forget about showing someone else (sitter etc) how to feed it!

Bottom line - I believe I can operate the VC quite well and once I got the hang of it I found it not too bad. I was disappointed with the burn times and the fact that the hottest part of the stove was the back of the stove - especially once I got some really good (3 year old) oak in there. So I took the extraordinary step of pulling out a <6 month old stove to replace it. If I lived alone, or at least was home most of the day instead of working full time with 3 small kids (soon to be 4) home and about I would likely have made a different decision, but I decided that burning should not be so difficult as that...

Time will tell if I made the right decision on my new stove, but based on what I have read here I think the fireview is a much better match for my lifestyle. Everyone has to make their own decisions, but I have advised folks away from the everburn style stoves if you are aiming for simplicity and 24/7 burning.
 
PART 2

I know this is a lot to read and take in at first, but it really is a simple process. Basically, you're going to build a fire with nice dry kindling and some newspapers tied into loose knots. You can build a kindling-only fire and then add spits, or you can build a "top down" fire where you build up your kindling and paper on top of some splits. Either way, you're going to have your primary air control fully open (and maybe even have the stove door cracked a bit) so that the fire will draw in the greatest amount of air possible and produce a quick, hot, and clean burning fire with good draft.

Once you have an established coal bed, you'll begin to add larger splits to your fire. Having then added a good load of larger splits, you'll usually leave the primary air fully open until the wood becomes "fully engaged" with primary combustion. After a few minutes (again, with seasoned wood), the wood will have charred black on the outside. At this point you'll start reducing the amount of primary air you give the wood (at this point, my stove top thermometer is usually reading between 450-500F). I usually reduce the primary air in stages over a 20 minute period or so (depending on the species of wood, size of the splits/load, etc.). As you reduce the primary air, you'll notice that the fire "moves" from the bottom of the wood to the top of the wood. This is the secondary combustion - the gases and smoke released from the charred wood will meet the hot, secondary air coming out of the tubes and ignite. It makes a beautiful, hypnotic fire.

Some non-cat stoves have an additional lever that may control a sort of "heat output" or "thermostat" type mechanism built into the stove, but for the most part the only moving parts you'll have on a non-cat stove is the primary air control. You'll quickly learn your optimal air setting for the type of burn you want.

A catalytic stove will have an additional lever called a bypass lever. This lever simply allows the smoke from the fire to "bypass" the catalyst and go straight up the chimney. Until the cat becomes hot enough to burn the smoke, it will not operate properly. So, until you get the cat hot enough, you'll leave the bypass open. Once it's hot enough, you simply close the lever, which forces the smoke through the catalyst which is treated with a special substance to help the smoke to ignite at a lower temperature than in a non-catalytic stove.

Each type of stove has its advantages and disadvantages. Cats are renowned for their long burn times, for example. But some people don't want to take the catalyst out and clean it and/or replace it when necessary. Most cat stove operators will tell you that this is both quick and easy. I've never operated one, so I can't give you an informed answer.

As far as overfiring goes, most manufacturers will tell you at what temp you're overfiring your particular model of stove. Get a $15 magnetic Rutland thermometer from Tractor Supply and put it on the stove top. Overfiring is usually the result of: leaving the door ajar too long after you've started a fresh fire and walked away (which you should never do), leaving the primary air open too long with a full load fully engaged, or adding fresh splits to an already established fire in the middle of a burn cycle.

Do some reading here (broken link removed to http://www.woodheat.org/technology/woodstoves.htm) to familiarize yourself with the two types of stoves. Properly installed and properly operated with dry, seasoned wood both are easy to operate and, more importantly, SAFE to operate.
 
Great posts Pagey.

The everburn system that you read about was the VC system which is unique to VC and should be avoided. It is a shame that the VC stoves look so darn nice, if only they worked worth a darn.
 
Highbeam said:
The everburn system that you read about was the VC system which is unique to VC and should be avoided. It is a shame that the VC stoves look so darn nice, if only they worked worth a darn.

Harman has it too. They call it an "Afterburner".
 
BrotherBart said:
Highbeam said:
The everburn system that you read about was the VC system which is unique to VC and should be avoided. It is a shame that the VC stoves look so darn nice, if only they worked worth a darn.

Harman has it too. They call it an "Afterburner".

Which I believe has now been renamed "Fire Dome".....i think.
 
Delta-T said:
BrotherBart said:
Highbeam said:
The everburn system that you read about was the VC system which is unique to VC and should be avoided. It is a shame that the VC stoves look so darn nice, if only they worked worth a darn.

Harman has it too. They call it an "Afterburner".

Which I believe has now been renamed "Fire Dome".....i think.

Firedome in the cast iron Oakwood and the TL300 steel stove. Afterburner in the Exception steel stove. Kinda confusing.
 
any secondary burn that routes the exhaust to the rear of the stove is junk, cat or not. the best cat stoves i have ever run into are the woodstocks, as their cats are underneath the stove top, thus routing all that usable heat to a spot on the stove where it (generally) works the heat into the room and not the back of your hearth (they are also cast iron housings for the cat, which i will get into the housing in a minute!)... some of the Old and new CDW stoves routhe the exhaust in the same fashion, but there are too many parts in there for my liking... a good non cat stove with a simple tube style system and a baffle will work great for you. Most of these top load stoves you see out there (with the "firedome, afterburn or everburn et all" rear secondary) systems were all designed by old VC engineers... this must be a pretty good gig for them, cause they had one idea about 20 years ago and keep shooping it around and peddling it to all these companies that want to build a stove to compare to the VCs. ask the sales guy to let you touch the secondary burn chamber in these rear routing cat and non cat stoves which introduces 2ndary air or holds the cat in place, just touching the fragile fiber crud in the back, and seeing how you have to handle it several times a year to clean it, will turn you off from these units.
 
The plate steel cat stoves are pretty good too, consider the blaze kings and the buck stoves. None of that hokey ceramic jive. I love the simple cat access on the woodstock fireview.

Blaze king with a thermostat = happiness.
 
jakehunter said:
so, the Harmon and the Vc are the same stove in the way of control?

I'm far less of an expert here than others posting, but I want to throw my 2c in ...

I don't know that they are the same in controls, however as I'm reading this, they have the same theory of function - i.e. they are both 'downdraft' style stoves where the smoke etc is basically routed down and out the back of the stove (in theory across/through a hot bed of coals) to get good and hot where they meet up with some nice hot air being injected into them and the smoke gets burned up. This is one of the two main ways that non-cat EPA stoves work.

The other way is that they put baffles in and burn tubes. In this configuration (at least from my understanding and observation) the smoke is slowed down on the exit and swirled about in the firebox near the top where it is good and hot and pre-heated air is injected (through the burn tubes) into this where the burn takes place. From pictures I've seen and things I've heard this can make for quite a nice show to boot.

Now - my issue with the downdraft design (among other things) is that much of this secondary combustion happens in the back of the stove. Granted it does radiate towards the firebox in the front (otherwise the fire would certainly not produce enough smoke to keep it going etc) but I'm not sitting back there. With my VC I found (via the good ol' IR thermometer) that the hottest part of the stove during the active burn stage (everburn engaged prior to coaling stage) was always the back of the stove by far. This means that it is radiating it out there and putting a lot up the chimney. Granted I am using a sample size of one to draw wide conclusions on the design so take it with a grain of salt. However I would not condemn all non-cat stoves due to this - just those that are designed to put the hottest burn at the back of the stove. It simply doesn't really make sense to me.

Now, I am sure that not all stoves sharing the same theory of operation are designed the same and I may well have had the worst implementation of the design on my hands, but I also am quite convinced that there are better theories on which to design efficient stoves than this downdraft/burn in the back of the stove approach.
 
Highbeam said:
The plate steel cat stoves are pretty good too, consider the blaze kings and the buck stoves. None of that hokey ceramic jive. I love the simple cat access on the woodstock fireview.

Blaze king with a thermostat = happiness.

Larger Woodstock with a thermostat = Ecstasy
 
Todd said:
Highbeam said:
The plate steel cat stoves are pretty good too, consider the blaze kings and the buck stoves. None of that hokey ceramic jive. I love the simple cat access on the woodstock fireview.

Blaze king with a thermostat = happiness.

Larger Woodstock with a thermostat = Ecstasy

I don't know - having just moved my fireview up the stairs and into place, I would hate to know how much a larger stove would weigh... might need a crane to install it. But once in place it would be awesome I'm sure.

Hmm... if you put two Fireviews side by side what would the clearance need to be between them?
 
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