Heat Output: cat vs. non-cat

  • Active since 1995, Hearth.com is THE place on the internet for free information and advice about wood stoves, pellet stoves and other energy saving equipment.

    We strive to provide opinions, articles, discussions and history related to Hearth Products and in a more general sense, energy issues.

    We promote the EFFICIENT, RESPONSIBLE, CLEAN and SAFE use of all fuels, whether renewable or fossil.
  • Hope everyone has a wonderful and warm Thanksgiving!
  • Super Cedar firestarters 30% discount Use code Hearth2024 Click here
Status
Not open for further replies.

4barrel

Member
Feb 15, 2013
47
I was interested in maybe getting a new stove for the longer burn times. I would like to get a cat but I read on this site before that cats do not put out as much heat as non cats. Is this true? Comparing a BK Princess and a Pacific Energy super27 or a summit, how would these stoves compare regarding heat output and burn times.
 
  • Like
Reactions: Jon1270
A non-cat stove doesn't put out more heat. If the stoves are equally sized the output will be nearly the same. The difference comes when the air is turned down to low. The cat stoves will cruise low and slow, non-cat stoves are hard to slow down once they get cruising and. The Super27 is a good stove with burn times of 8-12 hours. The BK is gonna give you consistent 18-24 hour burns.
 
Pushed hard and running all out, cat stoves can be rated a bit lower for maximum btus/hr., though we are seeing this go away with new hybrid designs like the Cape Cod and the Progress Hybrid. If the goal is absolute maximum burn times at very low output, cat stoves are great, but to be fair you need to compare equal sized fireboxes. The Super 27 is one of if not the long burn champ in non-cats. It will come close to matching an equal sized cat stove like the Buck 20 or BK Sirocco 20 for burn time, but I would give the cat the edge here. This changes when you go up to the 3 cu ft capacity stoves. There the cat stove is an undisputed champ. At a very low burn the Princess is going beat the Summit by many hours. On the opposite side, for maximum btus/hr I think the Summit pulls ahead. Visually, well, in this case a Chinook 30 would be a better comparison.

It really comes down to a lot of factors. If you live in a climate where shoulder seasons are long and really cold spells are infrequent, then the Princess may be a good fit. The same would be true if you have a very well insulated house that doesn't have a dramatic increase in heating needs when it is cold and windy. But if filling the stove every 8-12 hrs is fine with you and you like to have extra horsepower for very cold snaps and want a great fire view, then a non-cat may be a better fit. If you have a wife that wants a decent visual in the living room, then you may need to throw out theory and balance aesthetics. ;)

Now you better go out and get a bag of popcorn, a 12-pack and a very comfy chair. This is a perennial topic that usually goes on for days.

BK Sirocco -1.8 cu ft, 30,407 BTU's/h constant output for 8 hours
BK Princess - 2.85 cu ft, 40,863 BTU's/h constant output for 10 hours

Progress Hybrid - 2.8 cu ft, 12,538 - 73,171 BTU's/hr, max 80K btus
PE Super 27 - 2 cu ft, not sure of the low steady btus (rated at 34.6K EPA) /hr. Max out 72K btus​
PE Summit - 3 cu ft, , " " (rated at 38.5K btus EPA), max out 99K btus.
 
  • Like
Reactions: Ashful
BK Sirocco -1.8 cu ft, 30,407 BTU's/h constant output for 8 hours BK Princess - 2.85 cu ft, 40,863 BTU's/h constant output for 10 hours
Is this the rating on high?
 
I would guess so, but I am not sure of the exact setting that they used to come up with this number. It could just be that BK is trying to provide a meaningful metric.
[Hearth.com] Heat Output: cat vs. non-cat
 
I'm not sure about the Siroccco but I've talked to a few people lately that run the princess with 24hr burns consistently. The houses they were heating were sized appropriately to. That rating would have to be on high I would think.
 
4barrel, I think you need to clarify 'long burn times' and 'heat output'. Subjective terms, and mean different things to different people.

Sounds like you are replacing a stove. What is it, how much are you heating, and is it doing the job?

Cat vs non-cat gets kinda boring. Days worth of non-stop reading here on the subject. Helping someone buy a new stove is much more interesting.
 
I have a Avalon Olympic right now, house is about 1600 sq ft. with no wall insulation( hope to take care of that soon). This stove works good, lots of heat, great convection system, but I cannot get more than a four hour burn. Checked for leaks and all. The short burn times are becoming irratating. I use hardwood, seasoned one and a half to two year dried.
 
You say 1.5-2 years seasoned. Is that split and stacked for that time? How are you running the stove? Do you cut the air back and get a good secondary burn? What kind of temps are you running?

Only asking, because that's a big stove and should do better than that.
 
That stove should be doing minimal 2x the burn times your getting.
 
Thermostatic dampers can really help on burn times if I am not mistaken PE uses them or a variation of them for longer burns.

Pete
 
4 hour of heating is no good, this is what you should get from your stove:

"Heating Specifications
Approximate Maximum Heating Capacity (in square feet)* 1,500 to 2,500
Maximum BTU's per Hour (Cord Wood Calculation) 74,300
Overall Efficiency (Oregon Method) 70.0 %
Maximum Burn Time Up to 12 Hours"

Before thinking about replacing your stove, you will need to find out what went wrong with your current stove. Is its performance degraded over time or was it a sudden change?

To compare various stoves you can refer to: (broken link removed to http://www.chimneysweeponline.com/wscompha.htm)
 
I have a Avalon Olympic right now, house is about 1600 sq ft. with no wall insulation( hope to take care of that soon). This stove works good, lots of heat, great convection system, but I cannot get more than a four hour burn. Checked for leaks and all. The short burn times are becoming irratating. I use hardwood, seasoned one and a half to two year dried.

What is the stove top when you reload? I'm not sure if you're a newer burner or not but new burners tend to believe once the load is down to coals it is done. Maybe start with walking us through the loading process and how you're turning it down. Include time intervals, temps at those intervals and pictures if you can.

I had a Lopi Endeavor(smaller than your Olympic) before my BK and while it couldn't hold a candle to my BK in terms of burn times it would easily go 8+ hours depending on the weather. I would have coals after 12 but it wasn't heating anything at that point. When it was cold it would hold temps for about 5-6 hours and decline after that.
 
Checked for leaks and all.
Have you replaced the door gasket? Even if you have, do a dollar bill test on it. The door gasket is really the only place for that stove to be leaking air.
 
I have checked for leaks and found none. Door gasket is super tight. I stack my wood in a criss cross pattern for good airflow. The stove has always burned like this since the day I put it in. Maybe the draft on it is to strong, it has 28 feet of stainless liner in it, i don't know. I will load it up with about 3/4 load, if I try to fill it completely it tends too run to hot. I will bring temps at stovetop to about 450-500 then close the air control, leaving just a crack open. It simply will not burn more than 4 hours. Stove top temps during operation are between 500-600 degrees. I reload between 300-350. Secondary burns are inconsistent, sometimes I get them sometimes not. Whether the secondary burn is on or not, the burn times are the same.
 
I have checked for leaks and found none. Door gasket is super tight. I stack my wood in a criss cross pattern for good airflow. The stove has always burned like this since the day I put it in. Maybe the draft on it is to strong, it has 28 feet of stainless liner in it, i don't know. I will load it up with about 3/4 load, if I try to fill it completely it tends too run to hot. I will bring temps at stovetop to about 450-500 then close the air control, leaving just a crack open. It simply will not burn more than 4 hours. Stove top temps during operation are between 500-600 degrees. I reload between 300-350. Secondary burns are inconsistent, sometimes I get them sometimes not. Whether the secondary burn is on or not, the burn times are the same.

Everything I have bolded, is your problem. Lets take this in steps:
1. Load the wood all same direction. If you can load with the splits ends facing front to back or North to South as they say, you will be able to pack the wood in tighter and higher. Criss cross is just giving it too much air, and also leaving too much air space that could be filled with wood.
2. Before you blame the stove, and exchange it only to have the same issues, learn the stove and the best ways to burn it.
3. I have 27' of rigid insulated liner, and yes it drafts hard sometimes, but I never get less than 12 hour burn times, unless I don't do a full load and use soft wood. So liner height should not be an issue.
4.Load it up full with LARGE splits. Criss crossing with smaller splits will only last a short time, and it not the way to achieve a good long burn. Criss cross is for short, hot fires, as you are experiencing.
5.Try closing the air leaver completely, you won't constantly have secondaries, nor do you need secondaries constantly. If the stove rises to temp and heats the home, this is all that matters. Close that puppy all the way down and see what happens. Just know the difference between smoldering splits and glowing burning splits. These stoves burn top down. If it reaches cruising temp and holds, your heating and burning efficiently. and I guarantee it will last much longer than 4 hours. If it smolders and temp drops, open the air up again and get the temp a lil higher, then close back down again. You need to experiment and learn the stove and how to get the best burn out of it. Not just load it, get a temp, close it up some and expect it to magically do as you wish. Note, if you wood is not dry as it should be, your stove top temps will be lower and the wood will smolder, and you will need to leave the air open and lose burn times & temps. Again with 28' of liner, you should be needing to close that air lever all the way.
6. Patience is truly a virtue with wood burning. Try letting is burn down to 200 or 250 before reloading. Again, with good dry wood, you should be able to have just a nice level NOT THICK AS HELL coal bed on the bottom, and load a new full LARGE splits load on the coal bed, and obtain what you seek to achieve.

Large splits , then fill in with mediums and smalls. The larges will consume firebox air space, and keep the fires from hell from coming and will also bring the longer burn times.
Before getting rid of a stove for issues that are not the stove, but the operator & most likely wood, put the time in to learn the stove. As I said, otherwise you will be complaining about the next stove, and the one after that, and the one after that. etc. etc.
 
I think when he said he stacks the wood criss-crossed he means out in the storage area, not in the firebox.

If you are to replace the stove, the PE super firebox is a great choice for your home as is the BK line. Both are great stoves, best performance in their class, that being best non-cat and best cat.

The outputs that BG quoted are from marketing brochures and I fear that they are not apples to apples. In any case, max output is not a way to size your stove. Your current stove should be adequate for 1600SF once you get it dialed in.
 
Hogwildz, believe me I have tried it all, north south,east west. big splits small splits, you name it, the results are always the same. What I meant originally was I always thought that while cats burned longer, they don't put out as much heat as a non cat. Anyway. for all you Pacific energy owners, how long of a burn are you getting from you're super 27 and summit with useful heat say 350 degrees and over.
 
Mellow, no I have not. With a Olympic, you can use them as a insert or freestanding stove. I have it as a insert. I have become irritated with the short burn times and am looking at a Pacific energy if I can fit it in my fireplace.
 
What I meant originally was I always thought that while cats burned longer, they don't put out as much heat as a non cat.

So here's the deal with that. A stove of a certain size holds a certain amount of fuel and a fixed amount of total heat can be delivered from the stove to the room. The cat stove doesn't pull heat out of thin air, it just allows you to release the heat more slowly. You can also turn the cat stove up and get a much higher burn rate. You get a range of output. The non-cat must deliver the heat fast because the emissions equipment does not allow a slow burn. You choose a non-cat stove based on firebox size since your output is relatively fixed.

In the end, when you replace a non-cat stove with a cat you end up with a larger cat stove.

I replaced a non-cat 2 CF hearthstone with a 2.85 CF BK cat stove and am very happy with the improvement in burn times and even heat.
 
Cat stoves do not put out less heat than non-cats. They actually produce significantly more heat from the same wood compared to non-cats because they burn more of the volatile gases. The heat can be delivered at the same high rate as a non cat or, when a lot of heat is not required, at a slower rate for a longer period than a non-cat.

I would second the suggestion for a damper in your stove pipe. If you have tried all the methods that should give you a proper burn, and are using good wood, the remaining factor is too much draft. Inability to close the air down enough will result in too rich an oxygen supplky and too rapid transit of air through the stove, and resultant short burn time with a lot of heat going up the chimney. Likely also run relatively high flue temps. Certainly worth trying a damper before trying a new stove. Find the reason for the unsatisfactory burn times, since it is not inherent in the stove.
 
That is not universally true. The Englander 30NC for example burns cleaner than some cats like the BK King or Princess. But that is only part of the story. The other part is the heat efficiency of the stove. That is how much is radiated/convected into the room vs up the flue. Again this varies, some stoves being better than others. The Wittus TwinFire being a non-cat example at 93% efficiency.
 
  • Like
Reactions: rideau
I don' know what to do hear. I definately am not going thru another winter tending to this stove every 3 to 4 hours. Either way, if I want to get a Blaze King I will have to have my fireplace reworked to make it larger so the BK can fit in. Unfortunately, I don't think I have ever seen a good used BK on craigslist in my area. Wonder how much the fireplace rework will cost,aarrrggh.
 
Why must you rework the chimney. The princess uses the same 6" flue. Are you trying to stick with an insert?
 
Status
Not open for further replies.