Century CW2500 - Did I make a Mistake?

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Ok, so during some more test fires and learning, I managed to get my house to about 80 degrees yesterday (oops) - granted it was about 55F outside. Interestingly, I really do see a difference in draft based on outside temps. - the colder the better (duh).

Anyway, I was hunting around for some info on BTU rating and found this page:
https://www.hearth.com/calc/btucalc.html

From this, there is an example that states this:
"In this case, that direct vent fireplace that was 25,000 BTU's and 60% efficient (60% x 25,000=15,000 BTU's out)..."

I had no idea this is how the BTU/efficiency rating worked but it explains a lot.


Based on this, my old insert looks like this:
Low fire - 2400 BTU/hr x 63% efficiency = 1512 BTU
Med fire - 30500 BTU/hr x 48% efficiency = 14640 BTU
High fire - 156000 BTU/hr x 37% efficiency = 57720 BTU

The new one (with less segmented specs) is 65000 BTU and 76% efficiency (probably not directly tied) but if so, I am likely able to squeeze 38000-49400 BTU/hr out of the new stove.

Does this make sense?
Trying to get and idea of how close to/far from my new stoves capability really is from the old one.
 
OK, confession time. Inquisitor in my best CarTalk voice: Are you an engineer? :long: :lol:
 
BeGreen said:
OK, confession time. Inquisitor in my best CarTalk voice: Are you an engineer? :long: :lol:

Ha! How'd you guess? I am, actually. I have managed to hold off on the spreadsheets though I did geek out over some wood drying data graphs I found on this site recently.
 
No problem, you have company here. Have you already calculated out the total heat loss of the house?
 
Also, don't put too much faith in one magnetic thermometer. They're not always known for accuracy, but provide a good reference. Maybe check against an IR gun. They aren't that expensive, and another toy to play with.
Though with your known wet wood, it may be pretty close.
 
So in trying to work this situation out, I have found that rather than burning kindling down to hot coals and then adding your splits (as the owners manuals suggest) I get the kindling burning well then add the splits ASAP. It will then take a good 5-10 min. with the door cracked for the woods to take well. I then close the door and burn another 10 min. with air control wide open. Once THAT is happy, I shut the air down to 3/4 open and let the firebox build heat - up to about 350-400F (front of stove temp on an insert). Once I hit a good burn temp, I can shut the air down to 1/2 then finally about 1/4 and I get a nice burn and re-burn. My stove can now get up to 550F consistently with this method. Its a process for sure.

I imagine that with dry wood, the times between my air setting adjustments should decrease significantly?

I am currently waiting for a cord of dry(er) wood to mix in to be delivered…
 
Hey man, if it is working for you, go for it. The MOST important part of this whole thing is that you don't want to get complacent on your stack maintenance. Check often, brush as needed and keep that baby (stove) breathing as best you can.
 
Ok, so before this thread gets completely buried, lets assume the worst... when its the middle of January and I am panicking because its freezing in our house, what reasonably priced stove should I replace the Century with? I'm thinking (after the fact, unfortunately) that I need something with at least a 2.3cuft firebox to get the heat and burn time I am really after. The Osburn 2000 looks like a good fit. Any others in this price range to consider?
 
Jags said:
Hey man, if it is working for you, go for it. The MOST important part of this whole thing is that you don't want to get complacent on your stack maintenance. Check often, brush as needed and keep that baby (stove) breathing as best you can.

+1 . . . always keep up on the inspection and cleaning.
 
wrxtance said:
Our house is a 1.5 story cape. Stairway to the upper floor is attached to the room with the stove in it. We have an additional 5-600sqft to heat on the first floor - we have a pellet stove in there.

With better wood, I feel semi- confident that this stove will keep up but I'm starting to feel not-so-good about the firebox size. My understanding of "burn time" was different than what the manufacturer does too so the 4-6 hour range advertised for this stove isnt really true "burn time" it's more like "hot time".

Oh well, I'll do what I can. My chimney liner is good and the stove was $700 so if I have to upgrade to something bigger next year, it won't be a huge waste.

Umm . . . yeah . . . I think most of us were a bit snookered by the term "burn time" . . . we all see the term and then the figure . . . but none of us ever think when we're looking at those stoves for the first time to ask the sales person exactly what that term means . . . as you can see . . . different ideas for different folks . . . I know I pictured the firebox full of flames for the entire time . . .
 
Well, we had a pretty cold night - just dipped below freezing. I have been re-splitting my larger splits before loading and this really seems to have helped my situation. I had a good full load burning well at about 10pm, stove temps were approaching 575F (nice!). A reload at about 2am (when the baby was up feeding) with plenty of hot coals to ignite the splits right away. Another reload check at 6am had lots of big (glowing red) coals so I tossed 2 small splits in and opened the air 1/2 way to burn them down. 8am before leaving for work, I raked coals forward and jammed the stove back up.

Long story short, my house was plenty warm - like 72-74 upstairs and almost 78 downstairs. Thats a good feeling!

My two issues are probably time between reloads is a bit shorter than I had hoped for (NT advertises a 6-8 hour burn time) and managing the coal bed is going to take some time to figure out.

Thanks for the help...
 
Another update... finally hit the 600F mark on the stove over the weekend. I think the colder temps is helping the draft and my the wood has dried A LOT sitting in the basement for 3 weeks with the dehumidifier set at 45%. Things are rolling along.

Fun story - I decided to buy a cord of "seasoned" wood from a local tree company thinking it would be drier than what I had. Asked all the right questions and they gave all the right answers leading me to believe it was dry, seasoned wood. they delivered the wood 2 days later and I attempted to test burn 5-8 splits. The wood was soaked with rain (they said it was covered) and it was over 40% MC on a fresh split face (and smelled green). It was all wetter and greener than the wood I already had that I was not happy with! Needless to say, I am waiting for them to come and take it all back - I ain't paying for that! They were good about it despite them still being convinced their wood was perfect.

Bought some ECO bricks instead - these seem to give my stove the kick it needs to burn longer and hotter though I don't plan on making a habit of using these long-term...
 
Danno77 said:
I may be wrong about this, but I think those Century stoves are made by "StoveBuilders International" up in Canada. They make a CW2500 that was tested by the EPA and rated at 63% efficient and at 57,800BTU
http://www.epa.gov/oecaerth/resources/publications/monitoring/caa/woodstoves/certifiedwood.pdf

You are quite right SBI bought CFM plate steel stove business a few years ago when Century went up for sales. The BTU & efficiencies are EPA efficiencies listed using small quantities of soft wood. MFG's including Century list the EPA efficiencies as well as efficiencies obtained through testing using hard wood.

http://www.century-heating.com/product.aspx?CategoId=7&Id=522
 
Danno77 said:
I may be wrong about this, but I think those Century stoves are made by "StoveBuilders International" up in Canada. They make a CW2500 that was tested by the EPA and rated at 63% efficient and at 57,800BTU
http://www.epa.gov/oecaerth/resources/publications/monitoring/caa/woodstoves/certifiedwood.pdf

Interesting. The owners manual does state the 57,800 BTU/hr number burning the EPA test wood but 65,000 BTU/hr burning seasoned cord wood. This seems typical. However, they list "optimum efficiency" as 76% but the EPA test states 63% - not sure if THAT is typical...

Looking at that EPA listing, I am thinking the statements for my stove are perhaps better than typical. The Englander 13-NCi was another similarly sized insert I was looking at. They state 60,000 BTu/hr burning seasoned cord wood. I'd say the Century is "better" by the numbers if you are counting purely heat output and ignoring emissions...

Manufacturer - Model - Emissions - BTU - Efficiency

England's Stove Works, Inc. - 50-TNC Timber Ridge 13-NCI/50-TNC131 (Insert) - 2.6 - 10,000-29,200 - 63

StoveBuilder International, Inc. - CW2500, Solution 2.0-I - 4.7 - 9,600-57,800 - 63

Not quite sure what to make of all that but them's the numbers...
 
wrxtance said:
Not quite sure what to make of all that but them's the numbers...
LoL, same here. I'm not versed in the efficiency percentages more than to know that they assign all secondary combustion units the same 63%, higher for the cat stoves, and higher yet for the pellet stoves.

So, when I look at that EPA sheet, all the 63 tells me is that it must have secondary combustion.
 
wrxtance, if you've got room to keep it, don't have those guys take the wood. Put it up for next year or the year after.
So many of us have gone through the wet or not so dry wood situation it boggles the mind. I think we've all been conditioned to believe advertisers when they tell us their product is the bestest, goodest, _______
fill in the blank thing in the world.
You're finding (as all of us have) that the wood needs to be DRY, to perform the way we'd like. It still requires more work than just flipping the thermostat switch, but the heat is to die for. :coolsmile:
You're getting there, .......keep going.
 
PapaDave said:
wrxtance, if you've got room to keep it, don't have those guys take the wood. Put it up for next year or the year after.
So many of us have gone through the wet or not so dry wood situation it boggles the mind. I think we've all been conditioned to believe advertisers when they tell us their product is the bestest, goodest, _______
fill in the blank thing in the world.
You're finding (as all of us have) that the wood needs to be DRY, to perform the way we'd like. It still requires more work than just flipping the thermostat switch, but the heat is to die for. :coolsmile:
You're getting there, .......keep going.

I considered keeping it but I have about 8-10 cords of wood on tap that all I need to do is process. I want my $225 back is really it. New baby = tight on cash...
 
Jags said:
I think the above posters hit it. I will simply put these in order.

1.) check your wood (internally) for %MC - your fuel sounds suspicious.
2.) when you installed the liner, did you use a block off plate above the stove (and insulate)?
3.) 1.45 cuft fire box is small. The 65000 btu# was probably obtained from an all out "full burn". At 1.45 cuft and 65000 btu output, your probably going to have short burn cycles.
4.) The insert you have now is only capable of less than half the output of the old one, according to your numbers. Just say'in.
5.) Are you using the blower?

Welcome to the forum and stick around. We will help you obtain the best performance out of that new box that can be expected.

X2 on all of this.

Also in agreement that your temp gauge on top of the stove is inaccurate since the CW2500 blows out air beneath it.

I have the older CW2500 that has the added side air intakes. I have the temp guage on the front (upper most righthand corner). I usually get up to 400-450 as an operating temp. Since there is noplace to put it on top, the upper righthand corner is the best spot, but it is still in accurate as one person already mentioned here. I don't know if it is 150 less as previously mentioned, but that seems like a good guess as any -- I wouldn't say its less than that.

However with the right wood (bone dry red oak in 3"x5" thick splits fully loaded) and wide open air to start it, I once (only once) accidentally forgot I still had the air wide open and I accidentally pegged the temp guage at 800.

I though have a 24' ceramic fiber insulated SS liner in a masonry chimney.

Normally, the 2500 will overheat the 400 sq ft room fine and slightly under heat the remaining 1200 sq ft on the first floor (because alot of heat goes up the staircase to the second floor hallway, but not the bedrooms).

Our CW2500 is used only on weekend evenings sometimes during a weekend day if were home and it's really cold outside. The first cleaning (which was after 2 seasons) yielded only a 4 cups of soot).
 
wrxtance said:
Danno77 said:
I may be wrong about this, but I think those Century stoves are made by "StoveBuilders International" up in Canada. They make a CW2500 that was tested by the EPA and rated at 63% efficient and at 57,800BTU
http://www.epa.gov/oecaerth/resources/publications/monitoring/caa/woodstoves/certifiedwood.pdf

Interesting. The owners manual does state the 57,800 BTU/hr number burning the EPA test wood but 65,000 BTU/hr burning seasoned cord wood. This seems typical. However, they list "optimum efficiency" as 76% but the EPA test states 63% - not sure if THAT is typical...

Looking at that EPA listing, I am thinking the statements for my stove are perhaps better than typical. The Englander 13-NCi was another similarly sized insert I was looking at. They state 60,000 BTu/hr burning seasoned cord wood. I'd say the Century is "better" by the numbers if you are counting purely heat output and ignoring emissions...

Manufacturer - Model - Emissions - BTU - Efficiency

England's Stove Works, Inc. - 50-TNC Timber Ridge 13-NCI/50-TNC131 (Insert) - 2.6 - 10,000-29,200 - 63

StoveBuilder International, Inc. - CW2500, Solution 2.0-I - 4.7 - 9,600-57,800 - 63

Not quite sure what to make of all that but them's the numbers...

I have to repeat... EPA does not test for efficiencies. If you go to the EPA.gov web site you will see that every single stove and MFG is listed at 63%. That is EPA's silly way of saying "if you buy an EPA certified unit, you are guaranteed to have at least 63% efficiency". It's a baseline figure.

Most MFG will conduct separate efficiency testing with seasoned mixed cordwood and certified lab results for whoever requests it.
 
+Fyrebug. That was my bad. I said EPA rated it at 63%. It's only been in the last few months that someone explained all that garbage to me, so i was confused before!
 
So I've come to the conclusion that I did make a mistake with the stove. Not really the stoves fault but more my lack of research. I think the two biggest factors are 1. My understanding of "burn time" and 2. The "misprint" of the firebox size of the stove. The last factor is - don't trust real estate listings for square footage of your home. For the past year and a half, I have been under the assumption that our main house was 1500 sqft - its actually closer to 2000 (19-something). Oops, may bad there I suppose. Even still, I am heating a portion of that area with the pellet stove in our foyer between the main house and the garage anyway so "theoretically" I am only looking to heat 12-1500sqft which should be within the capability of the stove.

My wood isn't helping the situation but I have bought plenty "grocery store wood" to confirm this stove ain't gonna cut it. The firebox size is the real killer here - the stove needs to be reloaded every 3-4 hours to even try to keep up when the temps go below 30F. I can technically hit the 6-8hr "burn time" advertised but its certainly not usable heat. If it was actually 2.0cuft, I might stand a chance, but at an actual 1.45 I am lucky to cram 4-5 med size splits in there (or about $6 worth of grocery store wood!) due to the sloped configuration of the firebox, the back is very low. This cramming typically does not create an ideal airflow situation anyway so realistically its usually 3-4 splits when there is a typical load of coals in the stove.

So, long story short, I am poking around for a stove with a 2.3 or larger firebox. I wish I wasn't constrained to an insert (but I am) otherwise this would be easy. The Flame XTD 1.9-i is at the top of the list since it if the best stove that fits the budget.

Thanks for all the help - I wish I asked more questions up front.
 
wrxtance said:
So I've come to the conclusion that I did make a mistake with the stove. Not really the stoves fault but more my lack of research. I think the two biggest factors are 1. My understanding of "burn time" and 2. The "misprint" of the firebox size of the stove. The last factor is - don't trust real estate listings for square footage of your home. For the past year and a half, I have been under the assumption that our main house was 1500 sqft - its actually closer to 2000 (19-something). Oops, may bad there I suppose. Even still, I am heating a portion of that area with the pellet stove in our foyer between the main house and the garage anyway so "theoretically" I am only looking to heat 12-1500sqft which should be within the capability of the stove.

My wood isn't helping the situation but I have bought plenty "grocery store wood" to confirm this stove ain't gonna cut it. The firebox size is the real killer here - the stove needs to be reloaded every 3-4 hours to even try to keep up when the temps go below 30F. I can technically hit the 6-8hr "burn time" advertised but its certainly not usable heat. If it was actually 2.0cuft, I might stand a chance, but at an actual 1.45 I am lucky to cram 4-5 med size splits in there (or about $6 worth of grocery store wood!) due to the sloped configuration of the firebox, the back is very low. This cramming typically does not create an ideal airflow situation anyway so realistically its usually 3-4 splits when there is a typical load of coals in the stove.

So, long story short, I am poking around for a stove with a 2.3 or larger firebox. I wish I wasn't constrained to an insert (but I am) otherwise this would be easy. The Flame XTD 1.9-i is at the top of the list since it if the best stove that fits the budget.

Thanks for all the help - I wish I asked more questions up front.
What's the budget?
 
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