Charmaster wood / oil furnace replacement options

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Pakmt

New Member
Oct 21, 2023
5
Eastern CT
Hello all,
Congratulations on a great site.
I came across this forum recently when we started looking at replacement options for our 30+ year old Charmaster wood / oil furnace.
Although it has performed very well for us over the years, its age, lower efficiency and the manufacturer being out of business are all factors in our search for the optimal upgrade.
Since dual fuel furnaces like our Charmaster seem to be a thing of the past we are thinking about going with one of the new EPA certified wood furnaces and a heat pump system (which would also replace our older central A/C system .)
From what I have read thus far, there are only 3 options that are currently EPA certified. The Kuuma, the Drolet and the Caddy.
We're hoping to get some feedback from someone who has already replaced an old Charmaster with one of these new options.
Thank you for your time and consideration.
Pete and Tess
 
I dont think it matters much what they are replacing, but you'll be hard pressed to find anyone that has installed a Kuuma that is anything but thrilled with it...the only way would be if you have a VERY high heat load and the VF is just too small...but if that's the case then that ole Charmaster would have been eating you out of house and home, so to speak. It is also the one that would last you another 30 years too.
 
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Hello Brenndatomu,
Thank you for the reply.

The Charmaster can make a lot of heat but to your point, it can also burn a lot of wood.
During a cold winter and using wood almost exclusively we could go through 8 cords.
Last heating season was on the mild side, we probably went through 4-5 cords but used very little fuel oil.

With what research I have done so far the Kuuma seems to be the front runner. The one concern I have is the "computer" that seems to be essential in controlling it. But that maybe impossible to get away from with any of the new efficient designs available now?
(It seems like everything has a microprocessor in it these days...)
The one thing I always liked about the Charmaster was the simplicity. While very little ever went wrong with it over the years, I could always get it going again with an off the shelf part from the local electric or HVAC supply house.

If a proprietary "computer" like the one on the Kuuma fails its not something I will be able to patch up with a new relay or a micro switch.
I will have to research it a little more to see if it can still operate in some kind of "manual mode" should the computer fail.

Although I do not expect to be around in another 30 years I do agree with you that based upon what I've seen of it so far the Kuuma will probably last that long.

Thanks again for your input.
 
The Charmaster can make a lot of heat but to your point, it can also burn a lot of wood.
During a cold winter and using wood almost exclusively we could go through 8 cords.
Last heating season was on the mild side, we probably went through 4-5 cords but used very little fuel oil.
I used 6-8 cords when I had the Yukon wood/oil furnace too...Kuuma is more like 4 cords, and much better temp control...not to mention only having to clean (check) the chimney 1X/yr.
f a proprietary "computer" like the one on the Kuuma fails its not something I will be able to patch up with a new relay or a micro switch.
I will have to research it a little more to see if it can still operate in some kind of "manual mode" should the computer fail.
As for the computer, yup, hard to get away from that anymore...good news is that the Kuuma computer is very robust and they claim to have an extremely low failure rate...and they can be repaired (by them) if it does go out...if its something you are worried about just order a spare board for it...last I knew they were $400 (probably more now)
 
Hello Brenndatomu,
Thanks again for your input.
It sounds like your Yukon had very similar characteristics to the Charmaster, right down to needing to clean the chimney a 2nd time at mid season.
Having to plan around getting a couple of mild days in January in order to shut it down had been a challenge in some previous seasons.
We would not miss that 2nd cleaning at all!

Making an additional investment in a spare computer board would not be an issue for me, but it sounds like it's not something we need to be concerned about.

The Charmaster was my first experience with a wood/oil furnace. (I had a simple wood stove in the finished basement of my previous home.)
I "inherited" the Charmaster when I bought this house around 1990. The house was built only a couple of years prior to that and the lot was littered with piles of mostly oak, all cut to around 24" long . There had to be 15+ cords easy, all stacked and ready to split.
It was left from when they cleared a space to build the house.
I was young and ambitious, with more time and energy than money, so I became an advocate for heating my home with renewable fuel long before "renewable" was even a term.

I was new to the area and my first challenge was, at the time, the only two local oil / HVAC companies would not service it because it was a dual fuel furnace.
Fortunately I discovered that someone I had gone to trade school with lived in the area and had started his own HVAC business after completing his apprenticeship.
He was one who would much rather teach you how to fish versus giving me one, if you were willing to make the effort.
I learned a lot from him over the years. He would be a tremendous asset today as I move forward with this upgrade but sadly he had to close his business several years back due to an aggressive form of dementia.

My initial challenge will be finding someone in the area who can "marry" the VF100 to whatever we decide to go with for a secondary heat source.
I have the original 6" flue (insulated SS) to use for the Kuuma, but no other flue available to use for a secondary oil furnace.
Propane would work, since we could vent it with PVC. We were leaning towards a multi zone heat pump system since the main zone could be incorporated in the existing ductwork along with the Kuuma, and the additional zones could replace our aging central A/C as well.

Perhaps my first step is to see if Kuuma has any installs close by to me who I could contact?
 
Perhaps my first step is to see if Kuuma has any installs close by to me who I could contact?
You could check with them, they might know of people in your area that have done it in the past...give them a call, very helpful folks.
I'm surprised you have a 6" flue, most of those old dual fuels were 8"
 
I dunno about the Charmaster, but I lucked out with the Yukon and was able to reuse the same 24" x 24" supply plenum on the Kuuma...only had to trim 1" off the bottom. Had to reconfigure all the return connections, but that was no big deal and I was able to DIY that.
If you have a sheetmetal (ductwork) shop in the area, they'd be able to do it for you...that or find an HVAC service that has a tin knocker (sheet metal worker) If you are handy you can buy most of the pieces prefabbed too...modifications are pretty easy with just basic hand tools, if you have a basic knowledge of sheet metal work (its pretty simple once you see it done...and special tools make it faster/easier, but most things can still be accomplished with very basic tools)
 
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The original paperwork for the Charmaster that I got with the house said a 8" flue was recommended.
I think going with that unit was probably an after thought for the people who originally built this house.
(I have spent the past 30+ years correcting some of their design and build flaws...)
I asked Charmaster about it shortly after I bought the house (the owner /founder of the company answered the phone way back then) and he said it would be fine with the 6" flue as long as I had sufficient draft.
I have kept the flue clean and it has worked very well all these years.

I will give Kuuma a call today.

Thanks again for taking the time to share your experiences.

May I ask how long you have had your VF100?
And what you use for a secondary heat source?
 
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May I ask how long you have had your VF100?
And what you use for a secondary heat source?
2017 (IIRC)
And oil...rarely.
 
Years back I did a hot air system in an outbuilding, so I have some experience with DIY sheet metal ductwork.
I agree, it's looks complicated initially but once you see how the prefabricated pieces go together it's not that difficult.
Back then I was able to do all the modifications and install with just hand tools.
Now that I am at that age where working smart trumps working hard, when I get to that point I will leave the tin snips in the tool box and invest in some power shears :)

I believe the plenum on the Charmaster is also 24" by 24", that would be a good start.

Thanks again,
 
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