Drolet heatmax 2

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Alexandergunn

New Member
Sep 24, 2020
8
ELGIN NB Canada
Hello I just installed a Drolet heatmax 2. Had my brick chimney relined to 6in non flex factory liner as it was recommended for the stove the chimney is 35ft tall with two 45s on the flue before it enters the chimney. Changed all my duct work from 10" to 6" as recommneded by manufacturer in the manual I am heating a 2400sf home. Before the Drolet heatmax 2, I had a 1970s enterprise fawcett.

My question is I don't find i get a lot of heat after I have closed the air damper is this normal? It does secondary burns very well and my wood is between 15% and 25% moisture as recommended by the manufacturer. Is it possible i have to much draft? Any information would be much appreciated thank you
 
More info on your setup? Basement install? Hooked up to return ducting? Have you checked the draft? Pics of your setup helps tremendously. Many knowledgeable people here to help get it running right will chime in.
 
Yes it is a basement set up. I used the old cold air return off my old furance. I have not checked the draft as I would have to buy the tool but I wanted to see what people think first. I have 7 hot air ducts coming off max allowed is 10 . Also after talking to the manufacture the unit is not air tight at all so they recommended if the furance was in a room I did not want fully heated to tape up any air coming out as you can see there was a lot Thank you
 

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With a 35' tall chimney it is very likely that you have (or will have) high draft...I highly recommend buying a Dwyer Mark II model 25 manometer to monitor your draft full time...they can be bought on ebay and the like for $25-30 if you wait/watch a bit...well worth the investment. The HM2 needs draft readings to be in the -0.04" to -0.06" WC range.
You will need to put a Field barometric damper on the stove pipe to control the draft...and with a chimney that tall, in cold weather even that may not fully do the trick...I've heard of people that have to run 2 dampers, either 2 baro's, or 1 baro and one manual "key damper"

And just so you have the proper expectations, the HM2 will not put out the raw BTU's that an old school unit would, the ducts temps will be lower...its more like "slow and steady wins the race"
 
And no, the furnace should make the best heat once the intake damper is closed...duct temps should be at their peak an hour or two into the load once the damper closes and stays closed (good secondary fire)
Make sure that the baffle board above the secondary air tubes is properly in place...if it got jostled out of place when the furnace was installed (or sometimes just from careless loading) it will certainly affect how it burns and heats
 
I am wondering if the way things are setup if the furnace is working in a closed loop that bypasses the house ducts. Is there a backdraft damper in the supply plenum of the old furnace to prevent this?

Also, what is the distance between the stove pipe where it enters the chimney and the ceiling or nearest joist?
 
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I am wondering if the way things are setup if the furnace is working in a closed loop that bypasses the house ducts. Is there a backdraft damper in the supply plenum of the old furnace to prevent this?

Also, what is the distance between the stove pipe where it enters the chimney and the ceiling or nearest joist?
No there is no damper in the cold air plenum. I just uploaded a picture it comes out a foot then a 45 then 18in then another 45 into the brick chimney
 
With a 35' tall chimney it is very likely that you have (or will have) high draft...I highly recommend buying a Dwyer Mark II model 25 manometer to monitor your draft full time...they can be bought on ebay and the like for $25-30 if you wait/watch a bit...well worth the investment. The HM2 needs draft readings to be in the -0.04" to -0.06" WC range.
You will need to put a Field barometric damper on the stove pipe to control the draft...and with a chimney that tall, in cold weather even that may not fully do the trick...I've heard of people that have to run 2 dampers, either 2 baro's, or 1 baro and one manual "key damper"

And just so you have the proper expectations, the HM2 will not put out the raw BTU's that an old school unit would, the ducts temps will be lower...its more like "slow and steady wins the race"
I'm definitely going to get one I figured it was my issue because of the hight of my chimney. I've also only used it 3 times haven't really given it a chance yet. Thank you
 
No there is no damper in the cold air plenum. I just uploaded a picture it comes out a foot then a 45 then 18in then another 45 into the brick chimney
Do the hot air supply ducts feed upstairs directly? Or do the feed the supply plenum on the old furnace.

How close is the stove pipe to the nearest combustible (joists?) in the ceiling?
 
Do the hot air supply ducts feed upstairs directly? Or do the feed the supply plenum on the old furnace.

How close is the stove pipe to the nearest combustible (joists?) in the ceiling?
They feed it directly from the new furance the only piece of the old furance i re used was the cold air return system.

The stove pipe is more than 18in anyway from combustible materials. The warm air ducts hang below the floor to there proper clearance.
 
They feed it directly from the new furance the only piece of the old furance i re used was the cold air return system.
It was hard to tell from the picture whether hot air was being fed into the old furnace plenum. That all sounds good and there's no need for a backdraft damper.
 
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What size is the cold air return pipe coming from the old furnace?
The return ducts should be ~25% (ish) bigger than your supply pipes...so if you are using (7) 6" supply pipes and each one is 28.26 sq. inches x 7 = 197.82 sq inches. That means your return air needs to be 247 sq inches or so...that puts you at (1) 18" pipe or (1) 15" square duct...or a bit bigger due to the (2) 90* turns...
 
But just to be clear, the return pipe size isn't causing your current issue...just something that may need addressed
 
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the return pipe coming off the blower is 12in then in the cold air plenum there is two 10in and one 12in return duct that go to the main floor.
Also have a large side door that I could pull off that would draw air from the basement. I pretty much just hook this furance up the same as my last one but I took the hot air ducts down to 6in. I might be expecting too much out of the furance.
 
I might be expecting too much out of the furance.
Unless your house is poorly insulated/air sealed, the HM2 should heat it.
There is always a learning curve, and sometimes a few bugs to work out on the setup when coming from an old school burner...and many people don't have as dry of firewood as they though they did...but if you are getting good secondary burn then you are probably not dealing with that.
And I don't know how much you have run it yet, but when I was running the HM1, I found that spending a minute cleaning the heatexchanger tubes once a week during the regular heating season made a noticeable difference. I miss how easy it was to clean the HX on that unit!
 
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Unless your house is poorly insulated/air sealed, the HM2 should heat it.
There is always a learning curve, and sometimes a few bugs to work out on the setup when coming from an old school burner...and many people don't have as dry of firewood as they though they did...but if you are getting good secondary burn then you are probably not dealing with that.
I think its just a learning curve with the furance. I'm starting to use it more and I am seeing that the hot air vent I have one the back side is not as hot as the rest I may need to relocate this one also the run of this vent is at the max that is recommended so I may have to install a booster fan. As long as I don't burn 14 cords again this year I will be happy. My old furance had massive holes in the smoke chamber. We just moved in a year ago and still learning. The house seems insulated pretty good and I replaced all the windows and doors last fall to new ones and under all the siding it was re insulated but it is a old farm house. This winter will be a trail period. I also have a 30nc Englander upstairs between the both of them ill make it work.
 

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I don't think you can physically burn much more than 6-7 cords per winter in the HM...same with any of the new EPA fireboxes.
Having the NC30 upstairs too is a sweet setup...I have a Drolet 1400i in the fireplace up stairs and tend to use that when we just need a little heat, (like here lately) or want some "fire TV", but if I don't feel like messing with it, then the oil furnace is up to bat. That, and I could use it as a booster as you say if things really got cold and my VF100 couldn't keep up...not very likely it seems.
Looks like that old unit doesn't owe anybody anything anymore! !!!
I found the front duct was the hottest on my old HM1...the back the coolest...the VF100 runs the hottest at the front too.
Good plan on the booster fan.
 
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I have a similar setup. Also have a 35 foot chimney. My baro is almost constantly 1/2 open to keep the draft down. When its cold and windy, even more so. I feel you would benefit a lot seeing what that draft is and getting it lowered.
 
My question is I don't find i get a lot of heat after I have closed the air damper is this normal? It does secondary burns very well and my wood is between 15% and 25% moisture as recommended by the manufacturer. Is it possible i have to much draft? Any information would be much appreciated thank you

I am in no way an expert, ask anyone around here.

I found that establishing the proper static pressure really helped. Properly setting static pressure slows down the volume of air passing through heat exchanger in the plenum, which allows the air to achieve a higher temp before being distributed to your house.

I will now the experts burn me to the ground.
 
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You will need to put a Field barometric damper on the stove pipe to control the draft...and with a chimney that tall, in cold weather even that may not fully do the trick...I've heard of people that have to run 2 dampers, either 2 baro's, or 1 baro and one manual "key damper"
Is this damper better quality than the vogelzang from Menards? I need one that actually works. Mine just seems to either stay open or shut no matter how I adjust it. Don't mean to hijack here, you can pm me if you like.
 
s this damper better quality than the vogelzang from Menards? I need one that actually works.
Yes! That VZ is a POS!