First-time stove buyer

[Chasm]

Hi
I spend winters in our house in the hills of a high plateau area of Mexico - Oaxaca. We have high ceilings and poor insulation in a house made of cinder block, perhaps 12-1400 sq ft including bedrooms. Nights for 3 months are in the low 40's - down to maybe 37 degrees on coldest nights. Days of course, warm and sunny. No one down there uses any heat, but we prefer not sleeping in socks and sweat clothes under piles of blanket. I'm considering a Drolet Myriad II.
I don't have the knowledge or experience to know what they mean by good for "900-2100 sq ft".... am worried about overkill regarding stove size, as 40 degrees is hardly a deep freeze. Would like house to get to 65 degrees.
Appreciate any advice!

 

[begreen]

Welcome.

I think the Myriad would be overkill. You will not be burning 24/7. A 2 cu ft stove will easily take the edge off the cold in the evening. Take a look at the True North TN20. It is a good value stove with a square firebox for easy loading. That should handle the nighttime heating easily. Note that the firewood should be fully seasoned and dry for the stove to work properly. Normally the TN20 will work on a 12ft flue, but in Oaxaca I would try to make the flue at least 15 ft high, preferably straight up. The high altitude will require good draft and a taller flue.

The Oaxaca area is pretty special. We spent one Christmas there and have fondest memories of that time. Do they still do the festival of the radishes?

 

[Chasm]

Thanks!
.
Was afraid Drolet would be too much. Have been trying to read up on TN20 (as you probably know, it's daunting with no reference/experience). Nobody seems to discount it. Is it so much better than a Pleasant Hearth with similar specs for half the price?

(was told they sell dried encino - a kind of oak - by 2 cargas, or the amount 2 burros can carry, at a very good price. Wood is burned pretty much to make tortillas, not for heat)

And yes, very special... they still have that crazy festival in the zocalo. We love it there, looking to stay for good

 

[begreen]

Given the high altitude I suggested a stove that will work (at sea level) with a shorter chimney system. SBI makes Drolet and also Century stoves. A medium sized Century will also work, but may be a bit more fussy about chimney height. They also have a shallower firebox which constrains loading pretty much to east/west configuration. The TN20 has a square firebox that can be loaded N/S or E/W. That said, Century makes good value stoves and the FW2700 would get the job done.

 

[Chasm]

That unit is certainly more economical. We would be sending the flue straight up on a 12' ceiling and a 15' height is no constraint. We could consider adjusting budget - Is there any other reason you recommend the NP? I also saw a Jotul F400 "like new" on a local Craigslisting with "full chimney system" for 1600 that I figure isn't firm. Is it risky to buy used? I will appreciate any suggestions
Thanks again

 

[begreen]

The F400 is a nice stove, but it really wants decent draft to perform properly. TheTN20 is a value stove at around $1000.

Have you thought about how the chimney will be routed and how tall it will be? That may cost more than the stove.

 

[Ashful]

Think small, hot and fast. This is one of the few cases where I will not recommend BK. Get one of the several 1.7 cu ft stoves on the market (eg NC 17) and be done with it.

 

[begreen]

Think small, hot and fast. This is one of the few cases where I will not recommend BK. Get one of the several 1.7 cu ft stoves on the market (eg NC 17) and be done with it.

The Englander 17VL is a 1.1 cu ft stove, but it would work with a mid-evening refill. It's a great value if the budget is tight. The 13NC is 1.8 cu ft and a good little heater, but it will want a good flue to perform well. Both are E/W loaders.

 

[Chasm]

Labor is wonderfully inexpensive right now in Mexico.Almost negligible... materials will cost, tho, that's why I thought of the chimney system. I don't know much about these things, but we were going to perforate the roof and go straight up - roof is at least 12' high there - how much higher should we go above the roof line? My knowledge of the physics involved is woefully inadequate.... what determines "a decent draft"?

 

[Chasm]

I read somewhere that Englander and Pleasant Hearth are the same company. So.... Drolet and Century also are from the same manufacturer. okay....... budget is tight, but we want to do this right.
I haven't seen the TN20 FOR UNDER $1350.

 

[begreen]

I read somewhere that Englander and Pleasant Hearth are the same company. So.... Drolet and Century also are from the same manufacturer. okay....... budget is tight, but we want to do this right.
I haven't seen the TN20 FOR UNDER $1350.

They are not the same company. Drolet, Century, Osburn, Enerzone are all made by SBI. But Englander doesn't make Pleasant Hearth which is a GHP stove. True North is made by Pacific Energy. Last I checked our local price is just under $1k, but we are close to the manufacturer. NY is on the opposite coast. Call some local PE dealers for pricing.

 

[blades]

3/10 rule 3 ft higher than the highest thing in a 10 ft dia circle. Draft is a variable , many things can an do affect draft. Externally to house envelope- trees, location, style of roof, adjacent buildings, prevailing air currents. Inside - exhaust fans , tightness of home envelope, fuel, condition of fire in stove at any given stage, flue type and length- insulated or not. Basement installs are the most susceptible to draft problems along with external flues of metal or block that are not insulated.

 

[begreen]

Draft is a variable , many things can an do affect draft. Externally to house envelope- trees, location, style of roof, adjacent buildings, prevailing air currents.

And altitude

 

[Highbeam]

A large part of my heating season has overnight lows around 40. That’s plenty cold to burn wood. I too use nothing but wood for heat and we burn even when overnight temperatures are only upper 50s or even warmer.

Let’s not assume all of Mexico is so hot. The op’s home has a tall ceilings and is built of uninsulated masonry. He will need a decent sized stove to raise the temperature and then hold it overnight.

1400 sf, 12 foot ceilings, is equivalent to a normal 2000 sf home. No insulation! Masonry! Come on guys, he could use an nc30.

 

[begreen]

The difference is that days are sunny and temps warm up nicely. The masonry holds solar heat as well. That's why most living there don't have heat. The roof is 12 ft high but I didn't read that the room is unless there is no ceiling.

 

[Highbeam]

Look again, post #5 says 12’ ceiling.

If it warmed up enough during the day he wouldn’t need heat at night.

You can always burn a small fire in a large stove but you’re screwed with a small stove.

 

[hikingguyantonio]

Perhaps some closed cell rigid insulation board for the roof/walls would be your best help to hold heat and a fan to drive it down.

 

[Ashful]

If it warmed up enough during the day he wouldn’t need heat at night.

No matter where you live, many houses will be built with insulation envelopes just a little less adequate than they should be.

You can always burn a small fire in a large stove but you’re screwed with a small stove.

I see that said a lot here, but I don’t buy it for many of these more extreme cases. A big stove still needs to reach a sufficient temperature for secondary combustion to occur, and a fire as small as the OP may need might never get it there.

 

[begreen]

Look again, post #5 says 12’ ceiling.

If it warmed up enough during the day he wouldn’t need heat at night.

You can always burn a small fire in a large stove but you’re screwed with a small stove.

Thanks, I missed that. As noted most of the locals have no supplemental heat. With daytime temps frequently getting up into the 70's what they need is more of a chill chaser than a 24/7 heater.

That said, @Chasm if you like the Myriad II then it will work. It's overkill, but you can always build a smaller fire or open windows.

 

[Chasm]

Thank you gentleman for your interest and the information I am trying to assimilate.

It does get uncomfortable every night for three months, the nightly drop in temperature is about 30 degrees, it is cold enough indoors. The insulation is that bad. I have sworn I will not spend another winter w/o heat. It is true that the locals are quite accepting of the situation, but they don't like screens on windows or doors, while kitchens and sinks commonly have no hot water, even among the wealthy - it's a different culture.

I have read that building a smallish fire in a large stove could lead to a build-up of creosote. Is that true and would it cause me trouble?

Using the 3/10 rule, draft would be free of obstruction for perhaps 75% of circumference of the circle. There is a brick construction, a corner of which rises 5 1/2 feet, about 6-7 feet from where the pipe will come out (encloses a "tinaco", a plastic water tank that feeds water to house by gravity when electricity goes out.).
How would that affect draft?

Thanks again

I still have to figure out how to ship or carry this monster down there

 

[Ashful]

I have read that building a smallish fire in a large stove could lead to a build-up of creosote. Is that true and would it cause me trouble?

Modern EPA certified stoves operate on the principle of a secondary burn system. This secondary burn system was originally achieved by the use of a catalytic combustor, which will burn off all creosote and volatile wood gas at any exhaust temperature above 500F. It works great, but does create a maintenance issue, as the combustors must be replaced every 10,000 - 15,000 hours of operation if operated properly, sometimes much sooner if operated improperly.

In the last two decades, manufacturers have come up with systems (tubes, baffles) that will support a secondary burn without the use of a catalyst, albeit at a much higher exhaust temperature requirement around 1100F. This eliminates the requirement to maintain and replace a combustor, but very much limits how low you can burn the stove. The lowest setting on most of these non-cat stoves is equivalent to a medium burn setting on many catalytic stoves.

Now, the answer to your question in either case, is there is a minimum temperature you must maintain to avoid creosote problems. You don’t need to stuff a stove full to avoid these problems, but it’s false to tell someone they can build a very small fire in a large stove, as it will likely never reach secondary burn temperature. Do this once and it’s no big deal, but if it’s your daily mode of operation you will have problems.

If you’re buying non-cat, you really want to size the stove closer to your needs. Cat stoves have the advantage of being able to turn way, way down, to where the wood is just black charcoal giving off wood gas for the combustor to eat, but that’s not ideal for you either. I say that because these very low burn rates are of course associated with very long burn times, and many cat stoves can run over 30 hours on a single load of wood at a low burn rate... not what you want.

I really feel the ideal stove for you is a very small non-cat. You want a few hours of heat pumped into that house each evening, but you also likely want the stove dead-cold before noon the next day, right?

 

[begreen]

You can build partial load fires in a 3 cu ft stove, but there is not a lot of sense doing this if every fire is just a partial load. Considering the lowest temp for Oaxaca in January is around 47ºF with daytime highs around 78º, you may never run with a full load. A good 2 cu ft stove will put out plenty of heat with a full load and will burn cleanly with dry wood.

Whatever stove you choose, install it properly with 3 screws in every stove pipe joint. I would also bolt the stove to the hearth. There's too much shaking going on in Oaxaca to risk a hot stove moving.

 

[Chasm]

Found a TN19 for $899.Is there a big difference between the 19 and the 20?

 

[Chasm]

Modern EPA certified stoves operate on the principle of a secondary burn system. This secondary burn system was originally achieved by the use of a catalytic combustor, which will burn off all creosote and volatile wood gas at any exhaust temperature above 500F. It works great, but does create a maintenance issue, as the combustors must be replaced every 10,000 - 15,000 hours of operation if operated properly, sometimes much sooner if operated improperly.

In the last two decades, manufacturers have come up with systems (tubes, baffles) that will support a secondary burn without the use of a catalyst, albeit at a much higher exhaust temperature requirement around 1100F. This eliminates the requirement to maintain and replace a combustor, but very much limits how low you can burn the stove. The lowest setting on most of these non-cat stoves is equivalent to a medium burn setting on many catalytic stoves.

Now, the answer to your question in either case, is there is a minimum temperature you must maintain to avoid creosote problems. You don’t need to stuff a stove full to avoid these problems, but it’s false to tell someone they can build a very small fire in a large stove, as it will likely never reach secondary burn temperature. Do this once and it’s no big deal, but if it’s your daily mode of operation you will have problems.

If you’re buying non-cat, you really want to size the stove closer to your needs. Cat stoves have the advantage of being able to turn way, way down, to where the wood is just black charcoal giving off wood gas for the combustor to eat, but that’s not ideal for you either. I say that because these very low burn rates are of course associated with very long burn times, and many cat stoves can run over 30 hours on a single load of wood at a low burn rate... not what you want.

I really feel the ideal stove for you is a very small non-cat. You want a few hours of heat pumped into that house each evening, but you also likely want the stove dead-cold before noon the next day, right?

Pretyt much, yes. Thanks for a very clear answer

 

[Chasm]

You can build partial load fires in a 3 cu ft stove, but there is not a lot of sense doing this if every fire is just a partial load. Considering the lowest temp for Oaxaca in January is around 47ºF with daytime highs around 78º, you may never run with a full load. A good 2 cu ft stove will put out plenty of heat with a full load and will burn cleanly with dry wood.

Whatever stove you choose, install it properly with 3 screws in every stove pipe joint. I would also bolt the stove to the hearth. There's too much shaking going on in Oaxaca to risk a hot stove moving.

It gets a little colder than that every night up in the hills where I am, but your argument for the 2 cu ft makes a lot of sense