Units with Venting Ducts and effectiveness

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Feb 26, 2016
8
Wisconsin
Hoping I'm not asking a repeat question, I've found a couple posts similar to what I'm about to ask, but not the exact application, (for instance https://www.hearth.com/talk/threads/kozy-heat-z42-heat-duct-effectiveness.20869/) Sorry for the long start, just want to provide as much detail as possible based on my scenario, I'm sort of stuck in fireplace replacement limbo and I'm holding out that someone on the forum might have been in a similar situation.

I have a old builder grade wood buring unit from 1980 (year house was built.) We heat mainly with propane and enjoy the current fireplace for ambiance. I can get free maple and oak, I just have to go out and cut and chop, if I'm too lazy I can get it from a neighbor for almost free. That said the condition of the unit and chimney are starting to fail(36 years old.) I'm sure most of you could guess based off the year of the unit, but the current unit could be better labeled as a AC unit vs. a heating appliance. All considered I'd like to replace the unit and start new, unfortunately I'm running into numerous issues. Mainly is location and sizing, we have a 1500 sqft ranch house. The fireplace is in the family room, the family room is located on one corner of the house and is not central. I would like to buy an epa efficient fireplace since an efficient fireplace seems to run very similar to the less efficient models, but at the same time I would 1) Like to move some of the heat to other rooms since I'm spending money to have a new unit put in. and 2) Even with moving heat, not turn the room with the fireplace into a sauna (or worse.)

I have looked at multiple units that have heat venting duct options, Kozy, RSF, etc. What I'm curious about is, does anyone have any experience with how much of a dent in the overall heat output in the room with the fireplace does the additional ducting and heat draw make? The room the fireplace would be in is a 225sqft room(12.5x18 with a 8x4 bay window.) the room has a 5'x8' exit into a 48sqft mud room. from there its a 3'x8' opening into the kitchen and the rest of the house. Even running a ceiling fan on reverse, box fan inot the room, and just the fan on the furnace, i suspect that won't be enough to move the large amount of possible heat created. Ducting kits with fans that are optional with some of the units kits (970 on kozy and central fan on the rsf) seem like a no brainer to make sure heat gets to other parts of the house, but its left me wondering if that will be enough to keep temps below 90 in the family room... Also, most of the venting runs would be horizontal, not vertical, while the manuals I've read claim the blowers can even go in a downward direction, I'm curious if any has found this to cut into performance.

So I'm lucky enough to occasionally drink beer with a HVAC guy, I've bounced this off him and he was going to do some research to see if there was anything else we could potentially do, but admitted that fireplace heating isn't his specialty.

So if anyone has had a similar experience or setup, I'd love to hear back on what worked what didn't, if not thanks for taking the time to read! Worse case I either do nothing and we stop burning or I look at a less efficient unit with out the venting options.
 
That narrow door is the gating factor. It's going to keep the heat mostly in the room. One option to get around this is to duct the intake for the fireplace blower at the opposite end of the house. In ranches this is commonly at the end of the bedrooms hallway. That way warm air will constantly be pulled through the house and it will help even out temps.
 
Interesting, we've been looking at certain models that fit closer to the existing space and wouldn't require major reframing or spacing issues. The models we had looked at I don't believe have remote intake blowers as any options, so this is a new concept to me. BTW, is it safe to assuming you are mentioning the intake blower that draws cold air through the louvers/grating to the heat exchanger and back out the top? I see Napoleon has some models that have remote intakes for different locations in your house, but they don't mention if there are restrictions on the length of the run. (Hadn't looked at many Napoleons since they are a larger unit and the current framing/space might not work.)

Indeed, the opening into the kitchen is the pinch point. We bought the house 6 years ago, when we were looking we passed on many newer open concept houses, I just wasn't a huge fan and my wife was indifferent as well. Occasionally I kick myself for not being more open to the design, these last months for sure. Ironically one of my misguided issues with the open concept was all that extra vaulted ceiling air I had to heat...I wish I had some of that extra space/air to heat now.
 
Some ZC fireplaces have the option of using a remote blower instead of one built-in to the fireplace. This allows more flexible installation and removes the blower noise from the fireplace room. RSF for example offers this option with the Opel 3 fireplace.

Don't kick yourself about cathedral ceilings. They are just more space to keep warm and heat traps.
 
Thanks begreen, I'll keep checking around and post anything i find or try, if i do anything at all, I'm feeling rather defeated. Rsf was one of my initial favorites until i saw how much the excel 7" chimney cost, yikes in some cases as much as the unit! Location is everything and i just have a bad setup.
 
Thanks agains begreen!!

Wow that just might work. Reading some additional threads it sounds like the forced air kit really takes a good pull of the heat and the heating sounds more appropriate for my supplemental heating wants. I will have to check around with local dealers and installers to see if they carry Flame. If not i know Osburn is around here. What, if any, are the differences between Osburn and Flame other than price, I've seen some say its the same mfg box. Osburn seems to indicate a slightly larger minimum heating area, but thats about all I've come across.
 
Same parent company. The SBI Osburn and the Valcourt models are a bit more upscale.
 
Cant praise thus site enough, its helped me at least be compotent talking to these dealers at the different shops. Though I did have a talk with the wife about if we should just put the money into the boat fund we have for the criuser we want to get for lake michigan, was a losing battle... Sooo Osburn is still leading i guess.

One thing i've noticed though, been to three shops in a 40 mile radius, every single one has immediately steered me to the kozy heat z42, starting to wonder if there is some incentive to clear stock on those units?!

Also a couple dealers mentioned that the forced kit might move 40-50% of the heat, does that sound right or possible even?
 
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https://www.hearth.com/talk/threads...t-n-glo-northstar-fireplace-with-pics.149631/

we installed a ZC northstar fireplace including the remote ducting option (heat zone kit). we ducted the HZ kit straight down to the basement (to be finished later). from what i've seen using less than ideal firewood, we're able to get tolerable heat down into the basement. it's lukewarm air - slightly warmer than a furnace puts out.

if i were to choose again, i would not get it for one main reason: our current HVAC system does an admirable job when just using the fans only (no heat) to circulate the warm air from the fireplace area to the entire house, including the basement. it works remarkably well actually.

the other thing we notice is that cracking a window at the far end of the house on the same floor level as the fireplace does wonders to get the air to move throughout that floor. it's probably in the mid 70s in the fireplace area and right around 70 at the window that's opened (about 60ft away). granted, we now have a very open layout in our house (we just demoed every wall that doesn't enclose a bathroom or bedroom), so the air isn't trapped like you're concerned about. we also have cathedral ceilings above the fireplace (2/12 pitch). they absorb some of the heat for sure, but not enough to diminish the heat output for the upstairs area (1400 SF)
 
https://www.hearth.com/talk/threads...t-n-glo-northstar-fireplace-with-pics.149631/

we installed a ZC northstar fireplace including the remote ducting option (heat zone kit). we ducted the HZ kit straight down to the basement (to be finished later). from what i've seen using less than ideal firewood, we're able to get tolerable heat down into the basement. it's lukewarm air - slightly warmer than a furnace puts out.

if i were to choose again, i would not get it for one main reason: our current HVAC system does an admirable job when just using the fans only (no heat) to circulate the warm air from the fireplace area to the entire house, including the basement. it works remarkably well actually.

the other thing we notice is that cracking a window at the far end of the house on the same floor level as the fireplace does wonders to get the air to move throughout that floor. it's probably in the mid 70s in the fireplace area and right around 70 at the window that's opened (about 60ft away). granted, we now have a very open layout in our house (we just demoed every wall that doesn't enclose a bathroom or bedroom), so the air isn't trapped like you're concerned about. we also have cathedral ceilings above the fireplace (2/12 pitch). they absorb some of the heat for sure, but not enough to diminish the heat output for the upstairs area (1400 SF)

Awesome thread on the work you guys did. It really looks nice and it sounds like an awesome setup! Thanks for the response.

I think between your thread and me stumbiling on this thread, https://www.hearth.com/talk/threads/flame-monaco-xtd-zc-fireplace-questions.106154/ I probably have exhausted about as much info as I'm going to find, now it just comes down to the differences in setup and taking a leap of faith or getting cold feet. Thanks to both you and begreen for your responses, if I chicken out I probably won't be back on, but if we move forward i'll try and do a thread like yours (maybe minus the pictures of me demoing (and probably swearing alot as I tear the old one out)) and post the end results to hopefully help anyone else who might have a similar situation.

Thanks again.
 
Iron, I find this very encouraging! My wife and I are in the process of ZC fireplace selection and design, and one goal is to be able to distribute the heat throughout the house... as much as practical.

I'd been considering a remote duct down into the basement, where that warm air could be picked up by return air ducts and distributed by the furnace on blower-only mode. But a sales guy at a FP store told us there's no need for the remote duct, recirculating the air from the room with the FP would do a good job. We did have the HVAC guys put the return air grilles in that room up high on the wall to pick up warm air to circulate, so those are about 8' away from where the FP will be, and about 1' down from the ceiling.

You mentioned mid-70's at the FP and around 70 at a window about 60' away. Are all the rooms in your house kept at around 70 this way?

https://www.hearth.com/talk/threads...t-n-glo-northstar-fireplace-with-pics.149631/
if i were to choose again, i would not get it for one main reason: our current HVAC system does an admirable job when just using the fans only (no heat) to circulate the warm air from the fireplace area to the entire house, including the basement. it works remarkably well actually.
 
if you have a cold air return that close to the fireplace, i have little doubt you'll be able to get tons of hot air into the house's HVAC system. my CAR is about 20ft from the FP, located on the floor, sized about 25" x 9". however, there are a ton of people on this site with much more HVAC experience than me, so hopefully they'll chime in. i'm a newbie in the world of fireplaces/stoves.

yes, all the rooms on the main floor get to that same temperature by only using the FP (no blowers, just passive heat). it's pretty amazing to me. i think it is very important to have a FP surround made out of stone (or similar) --- something that can absorb the heat your FP is kicking out. that alone will add hours to the usable heat from the FP for something like an overnight burn.

FWIW: we're in the pacific NW, so it doesn't get too cold here. 2x4 walls with R-11 insulation, not air tight, 1979 construction. new windows.
 
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