WS Ideal Steel or BK Ashford for me?

Blowers???

 

Heat output per unit mass remains pretty constant in the same family of materials. If 50 lbs. of wood goes into a wood stove, my guess would be that there would only be 5 lbs. of charcoal left at the end of the wood buring phase. That amount of charcoal cannot put out the heat of 45 lbs (the wood burned) of wood.

As far as your perception of how your stove is heating, I would guess that most of the heat you feel from the 'coaling phase' is really coming from the wood burning phase but the soapstone has captured it and is radiating it later; you see the charcoal bed but the stone is at max. temp. from the earlier wood burn.

Brian

 

But the hybrids DO burn as a pure cat. stove at low burn rates. The firebox is black, the wood is pyrolysing and the cat. is burning the gasses being driven off the wood. Exactly the way a cat stove behaves. If the hybrid is turned up, the secondary burn starts, the cat. temp. drops (but to a point that is still higher than the firebox temp.) and the stove burns in two methods. Still, the hybrid in this mode is still at least as efficient as a pure cat. stove because on the simplest level, it does not matter what makes the heat (secondary flame or cat.) as long as the overall fuel consumption is kept at the same level.

Not all of us know that W.S. stoves do not / can not burn like a BK stove. Then again, some of us do not think any particular brand stove is magic and they must all follow the rules of chemistry....

Brian

 

"Of the total energy content of the wood you burn, about half is in the form of smoke, and half is charcoal."

 

I agree with that part for sure, and think about that all the time. There is definitely a 20 or 30 minute "delay" in the heat output from the PH stove. You have to consider that when adjusting the PH heat output/air setting. On cold starts (if I was away for a few days or something) I always turn it down before it gets to warm in the room, if you wait for it to be warm, your too late and it will be baking....

But that is not all of the result I'm seeing. Your estimate of only 5lbs of coaling weight left is way off I think. Maybe what we are calling the "coaling stage" is different? I assume the coaling stage when most all of the wood in the stove is glowing red. Sometimes that occurs pretty quickly into a burn, and it lasts a long time. I think a lot of the heat that comes out is being radiated from all those hot coals, filling 1/4 to 1/2 of the stove ! That is a lot of red hot coals radiating heat, as opposed to 2 or 3 splits out of 6 or 7 burning, during the burning stage.

 

One purpose of a Cat stove is to take the total heat of a load of wood and stretch that heat out over a longer period of time. Their heating curve is more flat. Its doesnt have a peak like a secondary air stove does. We need the secondary air stoves to have less of a peak and take that peak we dont need and add it to the end of the the wood load heat cycle. This is done by more mass in a stove, using stone that stores heat and also has mass or by a cat stove that allows the wood to be burned over a longer period of time. I know we are talking about Hybrid stoves but when we lower the input down to low levels they are mostly using the cat mode of operation.

 

I'm going to need to read up on the Hybrid stoves some more. From everything I've read to this point the secondary air does not ever get completely shut off. I've read countless posts on the Progress not burning low once the secondaries take over. The IS seems to handle this better from what I've read on it.

I didn't say they can't burn like a BK stove I said they don't burn low like a BK stove. If they do I'd love for someone to document the low burn since I love reading about 24hr+ shoulder season burns.

No magic in a BK stove, the control of the stove is just balanced enough to keep the cat active and consume a full load of wood when dialed down low without fiddling. I'm sure other manufactures could achieve the same thing if a low burn was what they wanted. I remember when the Lopi Cape Code was coming out, someone asked them(Todd maybe) if the stove would burn 24 hours and they replied with something along the lines of "we build stoves that can heat houses". I guess they didn't see the value in a long low burn.

 

They have a maintream look in the Progress Hybrid. Which is a remarkable stove, but it is more money. But, for heat capability, looks, long burns and adaptibility. it can't be beat. Left side or right side load, top or rear exhaust, Long legs/short legs, Ashpan or not ashpan. The Ashpan in and of itself on the IS and the PH is fantastic. Seriously if you are looking at 2K sq/ft and want it all and beautiful contemporary style, think about the PH.

Is the Ashford a hybrid stove? The hybrid design is not a gimmick, it is the best of both worlds. Long burn time and high efficiency of the catalytic with the combined high heat capability of the the secondary combustor, and the secondary is an impressive set of steel (?) plates, not just a few air tubes. (both the IS and the PH have this). So, if the Ashfiord is $2995 (is that the black one or enamel colors?) and you can get your head around $3290 for a Soapstone woodfired nuclear power plant, that comes in multiple color choices and is really awesome to look at.

Just my opinion, and I'm sure the Ashford is a really nice stove, but if you're not up for the looks of the IS think about a Progress Hybrid.

 

No, it's a cat stove.

 

Here ya go. A 'classic'.
http://detroit.craigslist.org/wyn/hsh/4845970534.html

 

Looks like a great deal for anyone within driving distance!

 

I live in Monroe county.

I don't think it's catalytic. No hole for the probe. I'm not sure what the bypass handle would look like on the old model, but it looks like there is some kind of knob in the second pic. And the poster mentions a screen, which wouldn't be with a cat stove.

But it will save thousands over the dealer

Love the charred handles and the custom 'ceramics'.

 

A few things for ya:
1. Your right the PH doesn't "normally" dial down low enough to get a 24 hour burn. I've had a handful of 24 hour burns, but it was mostly luck and a combo of using very large splits, 40's weather (lazy draft), and low settings and somehow getting a long burn out of it. But I can't do that regularly like you can on the BK.
2. You can turn down the air enough to kill the secondary's. If you have a fresh load in, and they are firing hard it might take a while (15 minutes..) to kill them and get back to a cat only burn, but you can do it by shutting down the air almost all the way.
3. You can close the secondary air pretty much 100% (less some leakage thru the screw holes.... in the air control obviously), what you can't close 100% is the primary air. Even when the air is shut off, there is still a bit of a gap top let air in.
4. I have a feeling the reason nobody else lets the low burns occur like the BK's do, is it is probably very difficult to tweak a stoves draft, air settings,... to make it work, and still get EPA approved, and not cause back puffs from getting choked to much. Just a guess, but I've wondered why also. I'd love to see Woodstock design the Progress Hybrid II, using a similar heat operated thermostat/air control. That would be the bomb!

 

BrianK did document a 24 hour (and a little more I think) burn in an Ideal Steel last year.

I think there is too much emphasis on the 'secondaries' in hybrid stoves doing something / preventing something that other, 'pure cat.' stoves do or do not do. The secondaries in a hybrid are easily stopped from burning, at least in an I.S., and while the secondary air supply remains open, there is absolutely no secondary burn taking place in the stove so all they are doing is actually supplying primary air. In fact, I think that is a better way to think of them- just another air supply to the firebox that happens to be in the back rather than the front as the primary is (the I.S. uses the primary as the airwash system and that air is introduced just above the door).

An Ideal Steel will actually burn extremely low and for a long time, and it is fantastic in shoulder seasons. My I.S. is the first woodstove I have been able to keep a fire going in without smoldering when the temp. is above 40F; the stove burns perfectly cleanly and puts out so little heat I have had it running when it is 60F outside without overheating the house.

I believe the idea that something has to be given up when comparing a hybrid stove to a non- hybrid, cat. based stove is just not correct. It really is the best of both worlds and can function extremely well in both modes IME.

Brian

 

Of course that 40 lb. / 5 lb. thing was just an example to convey the idea, not any real numbers.

And I absolutely agree that we have to decide when the wood fire ends and pure charcoal remaining starts. I personally call it the point at which no more fuel can be found in the stove that has any physical substance; put another way, it is when everything in the stove can easily be broken up with a tool. At that point I consider the fuel left to be pure charcoal and there is really not much heat value left. There is also not much mass left either although as you correctly point out, I cannot give actual numbers.

I believe the great amount of heat produced by burning wood comes from the consumption of the actual wood and the accompanying gasses driven off at the same time. By the time pure charcoal is left (nothing of any physical strength left inside the stove that cannot readily be moved around with a shovel for example), the majority of the heat is gone yet a pretty fair amount (scientific term ) of volume is still present; that is what causes our problems with charcoal building up when using a wood such as oak that produces a lot of coals.

Brian

 

Actually, the only reason you can't turn down low enough in the PH to get a 24 hour burn is because if you choke it off that much, you will get "puffs" cycling in the stove. There is not enough oxy in the box for fire, the. The gasses and oxy build up, and it all lights up at once, then goes black again and start over... It's not because you can't turn it down enough.

 

I have definitely had the "puff cycle" happen many times on my Progerss, until this year after I added a couple feet of pipe to the stack.
This almost completely solved the problem, now I get just an occasional backpuff.

I plan to add 1 more foot this weekend.

 

I was thinking it was a draft issue when Machria posted. I know the BK stoves are really draft sensitive when dialed down low.

 

What happens if you don't have enough draft on a BK dialed down low?

Mine is not a draft issue, my draft is fine. It's just that you can't choke the stove completely down, that's all. You just crack the air just a tad, and all is good.

 

The cat will probably stall if the chimney can't pull enough air on a low setting. Usually the guys with chimneys at the minimum chimney height have to burn their stoves at a higher setting.