Help with add on wood furnace

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Thank you for giving me a heads up on the Thermo-Control https://www.nationalstoveworks.com/product/warm-air-furnace
it appears to be exactly what I'm looking for. I filled out their contact form and I'm awaiting info. Main question is what if I don't use the hot water coils? Or for that matter how difficult is it to hook up to an electric hot water heater? I had one in my Charmaster wood/oil and didn't use the coil so eventually it burned/rotted through.......
My coils are not hooked up and they have not burned through. I have basic understandings of hydronic heating. It is to my thoughts that a water to water heat exchanger in a closed system would be necessary for heating DHW. An open system could be applied but you'd be evaporating a lot of water in your house.

that website falsely claims that indoor boilers and furnaces are not EPA regulated. I found very little info on the furnace you mention, I would seriously doubt their claims of it being a "downdraft gassifier".
In NY a heating unit is exempt from the EPA regs if installed in a structure. At least this is how it used to be.... an OWB was ok if it was grandfathered in, pre existing boilers. Any non gassifiers installed after regs were put in place were ok if in a structure. I haven't paid the regulations any mind in a number of years, so someone please correct me if I am wrong.

My indoor Thermocontrol was made in late 70s. Air intake is natural draft controlled by t-stat. Air enters front and travels down thru a pocket on back of door. There is a tube on each side of the stove, at the bottom, feeding fresh air to rear of stove, preheated by the coals.
Exhaust exits rear of stove from the bottom by traveling thru a chamber to the top. Opening at the bottom of chamber is where the preated air from the tubes exit. There is a bypass at the top of chamber for smokeless loading. It is not a true gassifier in todays standards but does have that effect.
 
In NY a heating unit is exempt from the EPA regs if installed in a structure. At least this is how it used to be.... an OWB was ok if it was grandfathered in, pre existing boilers. Any non gassifiers installed after regs were put in place were ok if in a structure. I haven't paid the regulations any mind in a number of years, so someone please correct me if I am wrong.
Everything changed starting in 2015, then things were tightened up more in 2017, the final round was 2020, and that one finished a number of manufacturers off...as in out of business.
Everything sold after May 15(?) 2020 has to meet the 2020 emissions limits in certified lab testing unless its sold as a coal burner, or some large outdoor wood boilers can still squeak by as "commercial" without meeting the limits...but they are supposed to be sold to business's only as I understand it...but I also don't think anybody is enforcing that too hard so far...
 
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Thank much for the replies. I was looking at the Heat Commander but how do I get around needing the plenum and all of the duct outlets? I only need/want an addon that has 1 outlet and 1 return air duct to connect to my existing ductwork. I would love to get the Drolet but is it customizable for my setup? I really miss the Charmaster wood/oil I had removed.
I spoke with Drolet about this. They said that it is possible to create a plenum with a single outlet. It just isn't supported and no guarantee. Think about it, they have to come up with a simple setup that they can create consistent results with. Custom plenums make that very difficult.

The Heat commander plenum is actually two pieces. The top piece with 6" supply holes slides over the bottom. You could fabricate a top piece that has a single supply coming off. You should be able to size it properly with some calculations. @brenndatomu has given good info on that.
 
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Heat Commander would be great but I don't have the overhead clearance for the plenum on that furnace nor do I have a need for 8 hot air supply ducts. If it had a simple outlet on the top or the rear it would work for me, therefore I am forced to look at other manufacturers. Unless Drolet could make a customization for an addon setup rather than the full plenum which looks like it's for a primary heat source.
How much clearance do you have?