modest upgrade from Hotblast 1557

Socratic Monologue Posted By Socratic Monologue, Feb 20, 2019 at 11:02 AM

  1. Socratic Monologue

    Socratic Monologue
    Member 2.
    NULL
    

    Dec 2, 2009
    44
    3
    Loc:
    WI
    We have been heating for ten years with a US Stove 1557, and have been fairly happy with it. Three years ago we added a Hearthstone Heritage in the open LR/DR, and love it. The Heritage is used for primary heat when the temps outside are above about 30F, and the two unit are both used when temps outside are below 0F or the wind is really blowing. There's a modern LP furnace for backup, and the LP and wood are separately ducted systems.

    I'm considering upgrading the HotBlast -- it is about 15 years old (it came with the house), though still runs fine, but it is hungry and dirty. The only reason I'd like to upgrade is to burn less wood and burn it more cleanly. We like that it can burn any wood of any size that fits in the box, and I know that this will not be possible in a more efficient furnace. The burn times are good enough for us -- a load at 11pm will usually leave a good bed of coals at 7am.

    The upgrade is constrained by the fact that the air ducting will not handle much more CFMs than the HotBlast pushes (1100cfm). The main trunk is only 8 x 14. This seems to rule out PSG, Drolet, and Kuuma. I'm not willing to reduct the house.

    The house is two story, 3000 sq feet, basement is partially heated, insulation is decent, house is 100 years old and not sealed overly well. The HotBlast/Hearthstone combination has been working well, temperature-wise. The wood furnace is installed in what used to be an attached garage (but of course we don't park vehicles in it; we have another detached garage for flammable equipment).

    I'm considering the Ashley AF700 or AF1440E/AF1500E (I don't know how these last two are different from each other). For both, required clearances, ducting, CFM and BTU output, etc are similar to the HotBlast, so should simply plug right in to our current setup.

    I'm most concerned about burn time compared to what we are used to. The AF700 has 3.6 cubic feet firebox; the AF1500E has 5.2 but is 10% less efficient on the EPA tests. The HotBlast has about 6.5 cubic feet firebox. I'm under the impression that firebox capacity is the primary determinant of burn time, but I don't know how changing to a unit with secondary combustion will affect this.

    Any advice is welcome.
     
    Stop hovering to collapse... Click to collapse... Hover to expand... Click to expand...
  2. 3fordasho

    3fordasho
    Minister of Fire 2.
    NULL
    

    Jul 20, 2007
    803
    212
    Loc:
    South Central Minnesota

    I would avoid any new EPA furnaces by USSC, Ashley, Shelter, Fire Chief - At least until there is a proven track records with their EPA models. Shelter and Firechief (same furnaces) were OK on their pre-EPA stuff but terrible on the recent EPA rated furnaces.

    At this point I would only consider the Drolet Tundra II, Heatpro, Caddy, Max caddy, or Kuuma furnaces. I have an original Tundra that heats 3400 sq ft in Southern MN in moderate temps (say down to 10F and with the wind in the right direction) Less than that or a south wind (no protection) and I really should have something bigger. With the 3.6ish cuft tundra I run 3 - 8 hr burns per day with plenty of coals for a restart. It will also burn any size cordwood that fits in the firebox provided it's dry, and there is a bed of coals.

    I have never owned a hotblast but the heat delivery characteristic would best be described as hot and fast vs the longer moderate output of a properly designed EPA furnace. So don't expect the furnaces I've listed above to raise temps quickly like your Hotblast may have done.

    As far as your ducting size, I know my Tundra would have no issue with the 8 x 14. The heat pro, max caddy, or Kuuma VF100 would probably require upsizing what you have.

    You should probably describe your chimney set up - the EPA furnaces are picky about chimney design.
     
    Stop hovering to collapse... Click to collapse... Hover to expand... Click to expand...
  3. Socratic Monologue

    Socratic Monologue
    Member 2.
    NULL
    

    Dec 2, 2009
    44
    3
    Loc:
    WI
    Thanks, Tim. That's all useful information to me. I am surprised that you say 8 x 14 duct would be sufficient; the Tundra is supposed to have no less than (6) 6-inch ducts. That is 168 sq inches, while a 8 x 14 is 112 sq inches. I looked at the Tundra II, but quickly scratched it from the list because of the ducting requirements. I'll take a look at it -- it seems a great unit.

    The chimney is straight up except for the 90 degree right at the rear vent of the furnace, about 4 feet of double wall leading into another roughly 15 feet of class A. All 6 inch, and all but the last 4 feet or so in an unheated but enclosed area (large furnace room, and attic space). I've never measured draft, but the HotBlast has a tendency to draw too hard, if anything.
     
    Stop hovering to collapse... Click to collapse... Hover to expand... Click to expand...
  4. 3fordasho

    3fordasho
    Minister of Fire 2.
    NULL
    

    Jul 20, 2007
    803
    212
    Loc:
    South Central Minnesota

    The original tundra has 2- 8" outlets for about 100 sq in. The tundra II has the same firebox and blower but they added a plenum on top which is just a sheet metal box for those 6-6" connections. You also have 4 blower speeds and corresponding cfm ratings to chose from. I think it will work just fine.

    Your chimney set up should be fine. I run between 15 or 18' 6" class A (two different installs) and one has a few more 45 els in the connector pipe. Both work well with out a barometric damper though on occasion in high wind conditions they may over draft a bit.

    The problem is when they get installed in oversize clay/block chimneys.
     
    Stop hovering to collapse... Click to collapse... Hover to expand... Click to expand...
    Socratic Monologue likes this.
  5. Socratic Monologue

    Socratic Monologue
    Member 2.
    NULL
    

    Dec 2, 2009
    44
    3
    Loc:
    WI
    What you say about the original Tundra makes sense to me.

    In this thread:

    https://www.hearth.com/talk/threads/ashley-tractor-supply-epa-indoor-furnace-info.156063/

    ...it is mentioned that the Clayton/Ashley looks a lot like the Tundra. Can anyone elaborate on whether the Ashley AF700/Clayton CF700 is just a knockoff of the Tundra sans automatic controls and multispeed blower? If it is, I'd definitely be on board with the Tundra II (sounds like an odd thing to say, but I'm feeling conservative regarding changing my furnace -- but I was comfortable switching US Stove products, and if the USS unit I was considering is simply a stripped-down copy of something much better, then I'd be comfortable with the better original).
     
    Stop hovering to collapse... Click to collapse... Hover to expand... Click to expand...
  6. brenndatomu

    brenndatomu
    Minister of Fire 2.
    NULL
    

    Aug 21, 2013
    3,915
    1,420
    Loc:
    NE Ohio
    That's kinda what I thought too.
    The Kuuma VF100 has a requirement of 180-200 sq in of duct...but also runs on low speed almost all of the time, which is ~500 CFM according to Lamppa...I think its a bit more than that personally. I've not used high speed yet.
    The only time it runs on high is if the Tstat calls for heat (I don't even have mine hooked up, and I don't think most people do) or if the fan control/limit switch trips out on high limit...and I'd bet most people never see that.
    The 180-200 sq in requirement might be for gravity flow on power loss too...dunno.

    Lamppa is supposed to be making the VF200 again very soon...it only uses one 8" duct pipe...rated to heat up to 3000 sq ft...I'm sure it would do the job in conjunction with your stove. If you were interested in one I'd call them tomorrow to see what the price would be if you preordered...they have a price increase coming at the end of the month.
     
    Stop hovering to collapse... Click to collapse... Hover to expand... Click to expand...
    Socratic Monologue likes this.
  7. Socratic Monologue

    Socratic Monologue
    Member 2.
    NULL
    

    Dec 2, 2009
    44
    3
    Loc:
    WI
    I emailed and got a timely response. The VF200 is hung up in the middle of EPA testing; the shutdown halted testing and it has yet to resume. Lamppa is hoping testing to be completed by early summer and anticipates having stoves available for next heating season. The price on the VF200 will remain the same as it is now ($4495).

    I did some reading and the VF200 is designed primarily to be ducted into a central heating system; this is apparently why the VF200 has only a 450cfm blower. I didn't mention it earlier, but my current setup has the wood furnace ducted independently of the central furnace. I separated the two systems shortly after buying the house, since the existing system was dangerous (wood furnace fed warm air into the cold air return of the LP furnace, and clearances on the LP ducts weren't up to code for solid fuel systems [2"]), and the only practical fix given the relative locations of the two furnaces was to disjoin them from each other.

    If my setup were a bit more straigtforward, the Kuuma might be a great fit, and I appreciate the idea.
     
    Stop hovering to collapse... Click to collapse... Hover to expand... Click to expand...
    brenndatomu likes this.
  8. brenndatomu

    brenndatomu
    Minister of Fire 2.
    NULL
    

    Aug 21, 2013
    3,915
    1,420
    Loc:
    NE Ohio
    I had a vf200 set up independently...it worked fine like that...was just a bit too small for my house, and didn't take my 22" firewood without cutting down each-and-every-piece! The blower only moves 450-500 CFM, but the air runs much warmer than the air coming off the VF100...sometimes 80* more!
    Dale had mentioned before that they have many people run the 200 as stand alone. He said one of the groups they are popular with is the "off griders" because the VF200 will run just fine on their solar powered battery banks.
     
    Stop hovering to collapse... Click to collapse... Hover to expand... Click to expand...
  9. Socratic Monologue

    Socratic Monologue
    Member 2.
    NULL
    

    Dec 2, 2009
    44
    3
    Loc:
    WI
    Can you say a bit about your house so I can compare? I'm heating about 2000 sq ft of a 3000 sq ft modernized 120 year old house to about 70F in temps not below zero (at that point, I fire up the Hearthstone).

    Didn't think of the wood length...I have 15 cords of 18-20 inch in the shed.

    I had read that about the higher air temps of the VF200. When I push the HotBlast, air in the duct is 200F a couple feet from the stove, and 150 at the floor vents. That warms the house, but the HotBlast has 1100 cfm (2 x 550cfm blowers).
     
    Stop hovering to collapse... Click to collapse... Hover to expand... Click to expand...
  10. brenndatomu

    brenndatomu
    Minister of Fire 2.
    NULL
    

    Aug 21, 2013
    3,915
    1,420
    Loc:
    NE Ohio
    1940 brick cape cod, 1200 ft basement, 1200 ground floor, 650 2cnd floor that was not being heated when I had the 200. The basement was mainly being heated by radiant, but there are a couple vents there too. Average insulation...not great, not terrible. We try to keep the house 72*ish. We typically only get a few days per year under zero...and I too fired up the fireplace stove when it got that cold.
    Like I said before, the main reason for upsizing to the VF100 was the wood length, the 200 calls for 16" wood ideally, 18" works, you can kinda creatively wedge a few pieces of 20" in there sometimes too...but 20" is it for sure.
    The other thing was that it was a bit small when it got real cold, and I knew that we would be starting to use the previously unheated 650 sq ft upstairs (that has so so insulation) this winter.

    Did you ask Lamppa what they thought about using the 100 with your smaller ducts?
     
    Stop hovering to collapse... Click to collapse... Hover to expand... Click to expand...
    Socratic Monologue likes this.
  11. Socratic Monologue

    Socratic Monologue
    Member 2.
    NULL
    

    Dec 2, 2009
    44
    3
    Loc:
    WI
    Not yet, but I'm thinking that I should -- or I should consider how hard it would be to upsize the ducts. I haven't gone downstairs with a measuring tape, but I think it would be relatively straightforward to replace the 8 x 14 main duct, though adding branch lines (there are only six 6" now = ~120 sq inches) would be more challenging.

    The cost difference between the VF100 and the Tundra is not insignificant, either. I'm certain the Kuuma is worth every penny, from what I've read, but being that I was happy enough with a HotBlast (which I'm less happy with now that I've started to consider the alternatives...), I'm not sure that I need that much of an upgrade.
     
    Stop hovering to collapse... Click to collapse... Hover to expand... Click to expand...
  12. brenndatomu

    brenndatomu
    Minister of Fire 2.
    NULL
    

    Aug 21, 2013
    3,915
    1,420
    Loc:
    NE Ohio
    And a Tundra would be quite the upgrade, let me assure you. The main thing you need to be aware of is that they need truly dry wood to work correctly...and they don't have the "raw horsepower" that the HB does...they'll heat your house, but its more of "some heat for a long time" rather than "a lot of heat for a short time"...tortoise vs the hare. Again, just so you are aware.
    The Tundra should do the job for you, but you might be toward the upper end of its capacity...maybe...you might consider the larger Heatpro too...but that would need upsized ducts for sure. Just throwing out option ideas...
     
    Stop hovering to collapse... Click to collapse... Hover to expand... Click to expand...
    Socratic Monologue and woodey like this.
  13. JRHAWK9

    JRHAWK9
    Minister of Fire 2.
    NULL
    

    Jan 8, 2014
    1,124
    743
    Loc:
    Wisconsin Dells, WI
    Where in WI are you? IMO, if feeding a hungry Hotblast can only keep your house 70° in above 0° outside temps you may be disappointed in any EPA furnace's output. Depending on where you live in WI, you've got to see temps below 0° quite often. Even in south-central WI we've been near or below 0 the past three mornings and according to the forecast will be again 8 out of the next 10 mornings. Like bren said, EPA furnaces don't have the raw HP of the older smoke dragons. They do provide more even/controlled heat throughout the burn, but lack the shorter lived blockbuster heat output of the smoke dragons.
     
    Stop hovering to collapse... Click to collapse... Hover to expand... Click to expand...
  14. Socratic Monologue

    Socratic Monologue
    Member 2.
    NULL
    

    Dec 2, 2009
    44
    3
    Loc:
    WI
    I'm just outside of Oxford -- about 20 miles from you. This winter has been fun for heating with wood, hasn't it (not sarcasm here -- I really liked the satisfaction of staying warm in -20F)?

    Last night -- low of 9F at the official station in Baraboo, but I think we are always about 3-5F lower here -- I went to bed at 10 pm with the house at 70 and this morning the LP furnace kicked in at 62F. (Edit: I just looked and Baraboo reported 3F shortly before I checked the temp). Just ran the Hotblast last night -- today with the warmth and sun we're just running the Hearthstone. I'm thinking a middle of the road EPA stove might be better for overnights, since the automatic damper and blower controls should level out heat production?

    The temp I want to keep the house at is 70. I think at 10F or so with no wind I could get it uncomfortably hot in here, but I haven't tried.

    Since I started using the HotBlast, I've been reading posts by @laynes69 who seems to be the king of HotBlast to Caddy upgrade, and I believe the Tundra is basically a stripped-down Caddy. His account of things seems to be very positive, but I do understand the point about the tortoise and the hare. We've been burning the Hearthstone for a few seasons now, and it does take a couple hours to get really warmed up, but then it throws a good amount of even heat even if we are erratic in reloading it.
     
    Stop hovering to collapse... Click to collapse... Hover to expand... Click to expand...
    brenndatomu likes this.
  15. Socratic Monologue

    Socratic Monologue
    Member 2.
    NULL
    

    Dec 2, 2009
    44
    3
    Loc:
    WI
    Thanks for the Heatpro suggestion. I just took a tape downstairs to check out the duct situation -- upsizing would be very challenging -- a good part of the run is sandwiched between the LP duct and a wall, with no alternative route. I'm ruling that out.

    As for dry wood: I'll bet JRHAWK9 might have as much wood for the next few years as we do; last August we had storms that put 16 tornadoes on the ground in a path that went though our property. We have about 50 good sized black locusts down, and some big old oaks that were in the process of dying from oak wilt.

    Anyone in central WI have a Tundra 2 running that I could look at? They are special order at Menards at this point in the season, so I can't even go look at a display model.
     
    Stop hovering to collapse... Click to collapse... Hover to expand... Click to expand...
  16. JRHAWK9

    JRHAWK9
    Minister of Fire 2.
    NULL
    

    Jan 8, 2014
    1,124
    743
    Loc:
    Wisconsin Dells, WI
    Howdy neighbor! A co-worker here is a retired Oxford prison guard. Outside of the one week of frigid temps at the end of January, it hasn't been too bad. December was warm, as was early January but the last week of January made up for it. I keep track of HDD's from the Reedsburg Airport. Looks like February is on pace to be the coldest since I've been keeping track (5 years or so). So far this heating season, December was the only month which was warmer than the 5 year HDD average. I will already be hitting the monthly average Feb HDD total in a couple days. Average is 1,121 HDD's, I'm at 1,041 currently with damn near a week of colder nights to go (after the next two warmer days). We too are normally cooler here than what Reedsburg airport states. We are in a lower part of a rural area. We hit -37° that one morning at the end of January. This winter is on pace to being the coldest cumulative HDD winter in the 5 years of keeping records.

    oh, I've got enough wood split/stacked already. ;) We didn't have any tornadoes around us, that I can recall anyway. We almost always have some stronger storms come through and take out a few trees though.
     
    Stop hovering to collapse... Click to collapse... Hover to expand... Click to expand...
  17. Socratic Monologue

    Socratic Monologue
    Member 2.
    NULL
    

    Dec 2, 2009
    44
    3
    Loc:
    WI
    Nice to meet a local on the big WWW!

    You beat us. The lowest I saw, IIRC, was -31.
     
    Stop hovering to collapse... Click to collapse... Hover to expand... Click to expand...
  18. JRHAWK9

    JRHAWK9
    Minister of Fire 2.
    NULL
    

    Jan 8, 2014
    1,124
    743
    Loc:
    Wisconsin Dells, WI
    I made sure to take a pic.....
     

    Attached Files:

    Stop hovering to collapse... Click to collapse... Hover to expand... Click to expand...
    sloeffle likes this.
  19. Socratic Monologue

    Socratic Monologue
    Member 2.
    NULL
    

    Dec 2, 2009
    44
    3
    Loc:
    WI
    Well, Menards has a 11% rebate again, and a store about 60 miles away has the last Tundra 2 in stock (a special order one is hard to return if I wanted to for some reason), so I bought it. Likely I won't install it until this burning season is over, but I'll update once I get it running.

    Thanks for all the help!
     
    Stop hovering to collapse... Click to collapse... Hover to expand... Click to expand...
    brenndatomu likes this.
  20. Gbawol42

    Gbawol42
    New Member 2.
    NULL
    

    Dec 16, 2018
    30
    19
    Loc:
    Saint Ignace, MI
    Wow there are no menards around me that stock it, good find!
     
  21. Socratic Monologue

    Socratic Monologue
    Member 2.
    NULL
    

    Dec 2, 2009
    44
    3
    Loc:
    WI
    The Menards in Johnson Creek listed one in stock on their website. I was going to go look at it, so I called and asked if it was on display; I was told it was boxed up. I then ordered it on the website for store pickup, just so no one would snatch it before I got to it. The next day, the store called me and said there was never any such stove in stock...:confused:

    I ended up special ordering it, and I did pick it up a couple days ago. I had to pull the blower off so I could fit it into my tractor bucket (Kubota BX) to get it off the truck; it is in the garage now, but installation is going to wait until burning season is over.
     
    Stop hovering to collapse... Click to collapse... Hover to expand... Click to expand...
  22. Gbawol42

    Gbawol42
    New Member 2.
    NULL
    

    Dec 16, 2018
    30
    19
    Loc:
    Saint Ignace, MI
    I am looking at doing this same exact thing, probably the next 11% off they have.
     
  23. brenndatomu

    brenndatomu
    Minister of Fire 2.
    NULL
    

    Aug 21, 2013
    3,915
    1,420
    Loc:
    NE Ohio
    And if you cash your income tax refund check at Menards, they will give you store credit for that amount, plus an extra 5% (IIRC its 5) My details might be off, but its something like that...EDIT: Yes, here it is...https://www.menards.com/main/tax-refund/c-19349.htm
    And just FYI, they often have the Tundra on sale, plus the 11% rebate too...toward the end of the heating season...not every year though it seems. I'm sure the 11% will be along shortly...
     
    Stop hovering to collapse... Click to collapse... Hover to expand... Click to expand...
  24. Gbawol42

    Gbawol42
    New Member 2.
    NULL
    

    Dec 16, 2018
    30
    19
    Loc:
    Saint Ignace, MI
    Do they put items on sale that they don't stock though? I used to see them on sale as well but it was when they were in the store.
     
  25. brenndatomu

    brenndatomu
    Minister of Fire 2.
    NULL
    

    Aug 21, 2013
    3,915
    1,420
    Loc:
    NE Ohio
    I've seen it in the past...well, it wasn't stocked in the store, maybe in the warehouse though...
     
    Stop hovering to collapse... Click to collapse... Hover to expand... Click to expand...
    Gbawol42 likes this.

Share This Page