Power outage use

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wil2007

New Member
Nov 22, 2021
3
Maine
I am considering a Heat Commander and Kuuma 100 for a new ranch home that I am building myself. First question would be, do either of these run if you lose power for an extended time. Second question, running ductwork yourself a possibility?
 

brenndatomu

Minister of Fire
Aug 21, 2013
6,574
NE Ohio
Well, they would both go down to "idle" with no power (at least I know the Kuuma does...and would certainly assume that of the HC) but the fire is likely going to continue on at a low rate for some time, unless maybe if you had just reloaded and it was not well established yet...I know the owners manual of the Kuuma recommends removing the air filters and the front cover so that the furnace can easily get airflow around the firebox...but if you properly design/install the duct system (good rise on the runs) it should still be able to "gravity heat" to some degree...heck, many old houses relied totally on gravity heat years ago. Here locally the Amish sometimes still build their homes to 100% gravity heat...they really liked the old model Caddys/Max Caddys because they could be bought will no blower, since they don't use electricity (the Amish) it would be a waste to have one sitting there unused.
There will always be times the power goes out when you are not home, or sleeping, so things need to be setup to handle those times...with no airflow past the furnace things could get hot quick...and that's another reason for the CTC (clearance to combustibles) specs listed in the manual. (for the furnace and the ductwork)
As far as if you can design and install the ducts...all depends on your skill set...I personally don't think its that hard, but if you are not familiar with how its done and don't have at least a few basic tools needed for the trade, it would be exceedingly difficult...might depend on what kind of permits/inspections are required in your local too...I'm sure there are places that they would not allow you to DIY it at all.
 
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woodey

Burning Hunk
Feb 8, 2018
218
ST. Lawrence Valley N.Y.
I am considering a Heat Commander and Kuuma 100 for a new ranch home that I am building myself. First question would be, do either of these run if you lose power for an extended time. Second question, running ductwork yourself a possibility?
If you lose power the Kuuma can be powered by a generator and also with power supplied by wind or solar. . Check out their website for videos on installation on ductwork.
 

laynes69

Minister of Fire
Oct 2, 2006
2,628
Ashland OH
In an outage the commander will shut down the fire. You're instructed to remove the filter if there is one. During an outage its recommended to have a smaller fire. The nice thing with the glass door is the heat output at the furnace.

I agree with Brenn, setting up the proper ductwork would be helpful especially in an outage. For us an outage and fire won't keep the entire house warm, but the basement stays warm which protects plumbing and keeps the downstairs warm.

I redid all of our ductwork years ago. Do your homework, it's not terribly difficult to do.
 
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peakbagger

Minister of Fire
Jul 11, 2008
6,616
Northern NH
The thing with ductwork is it really needs to be designed to match the flow in the equipment. Velocities need to be calculated and system resistance should be factored in. Sure you can push a fan to try to make up for too much resistance in the ductwork but it eats a bit more horsepower and the velocity goes up. That can lead to more noise and the duct flexing (it make a boom noise when you start up and shut down due to the duct oil canning. The opposite problem is low velocity, if its too big debris can accumulate on the bottom of the duct One good thing is duct insulation hides a lot of sins. Ideally even if it looks hacked up, as long as you seal all the cracks well, the insulation covers all the visual defects.

Ideally you find a supply house that sells prefab sections and then only need to cut them to length. The problem with using stock sections is that it rarely will fit tight up in cramped area.
 

brenndatomu

Minister of Fire
Aug 21, 2013
6,574
NE Ohio
The thing with ductwork is it really needs to be designed to match the flow in the equipment. Velocities need to be calculated and system resistance should be factored in
Some supply houses will design the system for you if you are buying from them...Menards will do it too, but I've never had them do it, so no idea how in depth they get with it...
 

Prominion

New Member
Sep 25, 2020
7
Boswell, BC
I am considering a Heat Commander and Kuuma 100 for a new ranch home that I am building myself. First question would be, do either of these run if you lose power for an extended time. Second question, running ductwork yourself a possibility?
I DIY'd a Heat Commander and ducting install this summer using the information provided in the manual to establish duct sizes, run lengths, clearances etc. It was pretty straight forward, I would definitely recommend a second set of hands while installing and a discussion with an HVAC pro to insure the system is properly set up and balanced. Note - my location in BC exempts wood burning appliances from permit requirements, this is NOT the case in most jurisdictions.
Power has gone out several times since install, as noted in the manual the HC shuts combustion air and dampers at power loss and recommends filter removal for unrestricted movement of distribution air. Having a full cold air return seems to help a lot. The fire definitely banks hard but we receive a lot of heat through the ducting...the furnace is in the basement which helps. We have full generator backup (necessary here in the sticks) so really not an issue for us but a fairly small generator or battery set up could run the furnace and blower in a pinch.
Good luck, the Heat Commander was a very good choice for our circumstance.
 

trx250r87

Burning Hunk
Nov 30, 2012
188
NE Wisconsin
When the Heat Commander loses power both primary air and grate air dampers slam shut, and only the secondary air opening would provide any air to the fire. I guess the small hole under the door would too but I don't think this would be enough to feed the fire enough air for real heat output.

I would install a UPS and some extra batteries.

Eric
 
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wil2007

New Member
Nov 22, 2021
3
Maine
Thanks for all the information. This is new construction planning. I have a new soapstone wood stove that was planned for main floor. I had been thinking that if I could rely on furnace alone that I might be able to eliminate stove and go with costlier KUUMA. Once again, thanks for all your insight.
 

brenndatomu

Minister of Fire
Aug 21, 2013
6,574
NE Ohio
I had been thinking that if I could rely on furnace alone that I might be able to eliminate stove and go with costlier KUUMA. Once again, thanks for all your insight.
To me the best of both worlds would be a furnace for normal use and a free standing stove for power outages, and occasional "fire TV"...unless maybe you could design the house around the stove to the point it would heat the whole place well...if doing that I think I would want to go with a high end stove though...like a soapstone lined cat stove, something like that...
 

wil2007

New Member
Nov 22, 2021
3
Maine
I am pretty much convinced that the stove will stay. It is a catalytic soapstone fireview from woodstock stove co.This will definitely heat the main living area. My thought is a wood furnace would give me an even heat throughout the house. I think that I will probably put a Rinnai direct vent in the basement to satisfy insurance co. I still have to check on that. Also wondering if forced air electric hooked up with wood furnace might be the way to go. all opinions welcomed, I only get to do this once in our retirement home.
 

brenndatomu

Minister of Fire
Aug 21, 2013
6,574
NE Ohio
Also wondering if forced air electric hooked up with wood furnace might be the way to go
That would be ok if you are just trying to satisfy the banks requirements for "automatic heat"...but beware that when any kind of electric resistance heat runs, it makes your electric meter spin like a turbine engine! I'd hate to have to use that much if you weren't able to make firewood any longer...some major change in life like that...
I'd be more inclined to do mini split system(s)...or maybe even put in an oil or LP tank (if its just for very occasional use) Mini split gets you cooling and heating though...