New Furnace Day: Drolet Heat Commander

[Matt78]

Wow, that's every last bit of energy out of that exhaust stream! I'm happy with 400-500 df (estimated) internal flue temp on my Morso after the built in heat exchanger. Once I have a properly sized insulated liner I will probably run it even lower.

I did see 400 on it yesterday

 

[JRHAWK9]

Wow, that's every last bit of energy out of that exhaust stream! I'm happy with 400-500 df (estimated) internal flue temp on my Morso after the built in heat exchanger. Once I have a properly sized insulated liner I will probably run it even lower.

Those flue temps are pretty typical of all newer GOOD furnaces. With a clean heat exchanger and extended pilot time with the computer set to minimum burn, I have seen flue temps as low as 280° internal about 12" from the collar.

 

[brenndatomu]

I have seen flue temps as low as 280° internal about 12" from the collar.

X2...have seen lower than that too...but then I realized that my temp probe needed cleaned and/or was pushed in too far (was at the bottom of the pipe...I try to keep it in the middle.

 

[JRHAWK9]

X2...have seen lower than that too...but then I realized that my temp probe needed cleaned and/or was pushed in too far (was at the bottom of the pipe...I try to keep it in the middle.

I remember those 250° temps....I was like



If I pull my probe out an inch it makes a difference in the temp it reads, as it reads lower. I have mine directly on top of the stove pipe inserted fully.

 

[brenndatomu]

I have mine directly on top of the stove pipe inserted fully.

I have mine directly on top of the stove pipe inserted fully.

Right...but my probe is longer I think...it will go clear to the bottom of the pipe if I let it.
(that will elicit a few comments I imagine...)

 

[JRHAWK9]

Right...but my probe is longer I think...it will go clear to the bottom of the pipe if I let it.

yeah, I was not blessed with a very long probe.

 

[ColCat]

New poster here on this thread, although I have posted hearth for some time. It has taken me a day just to get through this thread and I greatly appreciate the enthusiasm you have shown with this HC.

I currently have had a hot blast (my third wood furnace) for three years and the steel air channels that feed the stainless secondary burn tubes are rotting out. I have ordered an HC and it will be delivered next Monday. I wonder if you could kindly indulge me with some questions.

My current hot air delivery is via two 8" round ducts that connect to two different branch rectangular ducts. By my calculations, that only gives me 100 cubic inches when I need about 170. How have others handled this? Also, it seems to me that it would be much easier to connect these directly to the top of the HC box instead of creating some kind of octopus with all these 6" ducts.

Second, I don't currently use a barometric damper. Looking back on previous hearth posts, one reads: "A barometric damper should never be installed on a wood stove. It will allow cool air into the flue, both slowing flue gases and increasing the likelihood of the smoke condensing and forming creosote. A barometric damper will also cause very rapid feeding of a chimney fire if one were to start. (posted on Feb 24, 2009.)" Why is it now OK to install one in an exhaust stovepipe?

 

[maple1]

That's likely comparing a somewhat dirtier burning wood stove to a clean burning furnace. There should be next to nothing in the exhaust stream of an EPA furnace that would condense to creosote.

 

[andym]

The owners manual for both of the current EPA wood furnaces specify a BD to control strong draft. The HC specifies no more than a .06 draft. Most installs will require or at least benefit from installing a barometric damper.

 

[brenndatomu]

Most installs will require or at least benefit from installing a barometric damper.

Especially tall chimneys...which you tend to have on wood furnaces in the basement...and there really is no other good way to control draft on a machine that is hooked to a tstat, and can change the air intake on its own...when that happens a closed manual damper could be disastrous.
Kuumas come with a BD...I think they want you to use it...

 

[trx250r87]

New poster here on this thread, although I have posted hearth for some time. It has taken me a day just to get through this thread and I greatly appreciate the enthusiasm you have shown with this HC.

I currently have had a hot blast (my third wood furnace) for three years and the steel air channels that feed the stainless secondary burn tubes are rotting out. I have ordered an HC and it will be delivered next Monday. I wonder if you could kindly indulge me with some questions.

My current hot air delivery is via two 8" round ducts that connect to two different branch rectangular ducts. By my calculations, that only gives me 100 cubic inches when I need about 170. How have others handled this? Also, it seems to me that it would be much easier to connect these directly to the top of the HC box instead of creating some kind of octopus with all these 6" ducts.

Second, I don't currently use a barometric damper. Looking back on previous hearth posts, one reads: "A barometric damper should never be installed on a wood stove. It will allow cool air into the flue, both slowing flue gases and increasing the likelihood of the smoke condensing and forming creosote. A barometric damper will also cause very rapid feeding of a chimney fire if one were to start. (posted on Feb 24, 2009.)" Why is it now OK to install one in an exhaust stovepipe?

I'm running three 8" round ducts from the Heat Commander into the main trunk of my gas furnace. I also didn't seal up the top of the plenum very well, where there are air leaks from the ten 6" take-offs that I did not use.

Eric

 

[JRHAWK9]

Wow, that's every last bit of energy out of that exhaust stream! I'm happy with 400-500 df (estimated) internal flue temp on my Morso after the built in heat exchanger. Once I have a properly sized insulated liner I will probably run it even lower.

We finally are getting a couple days of colder weather so I was able to do some back to back to back loadings on coals. Woke up to 9° this morning.

Here's a graph of my flue temps and supply temps with the Kuuma set on minimum burn. It's been almost a couple months since I cleaned the heat exchanger. Red are flue temps, blue are supply temps.

- 7:45pm last night. Started a fire in a warm firebox and loaded 18.7lbs.
- 10pm last night. Loaded 52.6lbs for the night on a bed of nice coals.
- 7:15am this morning. Raked coals forward (to burn them off faster).
- 8:50am this morning. Loaded 48.9lbs.

The peaks and troughs of the flue gas temps are the computer automatically opening and closing the primary damper in order to keep firebox temps at whatever setpoint I have the computer set to, in this case minimum.

Just supply temps. Spikes in supply temps are when I shut the blower off whenever I open the door. This is also how I know what times I'm doing things like loading and raking coals forward when I look at these graphs later on.

House was 74° when I got up and is still 74° almost 40 minutes after loading the morning load. 11° outside now.

Just happened to glance at my remote temp monitoring now and my flue gas temp was 318°.

 

[JRHAWK9]

Mine runs about 200 to 300 degrees. My T1 if I remember right. Was anywhere from 300 to 550 degrees. I'm going to shut it down Wednesday and add the baro. Curious to see what the pipe looks like after a month of burning!

Where you place the probe and to what depth you place it in the stove pipe makes a difference on what you see for temps. In my experience, placing it within 12" of the collar and ON TOP of the pipe inserted so the probe tip sees at least the middle of the pipe makes for the most accurate (higher) temps. If you place it on the bottom, further down stream or not inserted far enough, you will be showing lower temps. I can drop my metered temps 50° by simply pulling the probe out maybe 0.5" to an 1".

 

[woodey]

Spikes in supply temps are when I shut the blower off whenever I open the door

Wondering why you are shutting the blower off prior to opening the door?

 

[JRHAWK9]

Wondering why you are shutting the blower off prior to opening the door?

I have a couple small 4" ducts above the door which reclaims some of the heat off the face of the furnace and puts it in my return air. I just don't want any potential smoke spillage to be sucked up and sent throughout the house. It's just a habit I got myself into.

 

[brenndatomu]

I have a couple small 4" ducts above the door which reclaims some of the heat off the face of the furnace and puts it in my return air. I just don't want any potential smoke spillage to be sucked up and sent throughout the house. It's just a habit I got myself into.

That and you took the smoke flap off too, right?

 

[woodey]

I have a couple small 4" ducts above the door which reclaims some of the heat off the face of the furnace and puts it in my return air. I just don't want any potential smoke spillage to be sucked up and sent throughout the house. It's just a habit I got myself into.

After I posted my question I remembered what your setup looked like and assumed it had something to do with that.

 

[JRHAWK9]

That and you took the smoke flap off too, right?

yep, that too.

 

[ColCat]

Can the Field Controls barometric draft controller fit into a standard 6" stovepipe tee? I purchased the US Stove draft controller, but can return it if the Field Controls unit is that much better.

 

[brenndatomu]

Yes

Can the Field Controls barometric draft controller fit into a standard 6" stovepipe tee?

Yes.

I purchased the US Stove draft controller, but can return it if the Field Controls unit is that much better.

Not familiar with the USSC baro, but they are not known for high quality...just cheap price.
EDIT: just looked them up...look the same as the VZ unit...get to thinking about it, I think USSC owns VZ now...

 

[Rockstar1346]

Hi everyone,

few more answers here

Caddy Advanced and Caddy Advanced CR

Many of you are speculating about the Caddy Advanced and Advanced CR. I cannot tell much for now, but both will share the same firebox and the same controller with the Heat Commander. As it is currently, our PSG line is for HVAC instead of hardware store. We planned to offer in the PSG line an entry level furnace (Advanced) and the CR which will come with all the bells and whistles and more. For sure, the Advanced won’t be exactly the same as the Heat Commander it will be better suited for HVAC instead of DIY as most of you are. We don’t have the release date for now, the Advanced will come first and the CR will be available later. We hope both will be out on the market for next heating season.



Smaller or bigger

Ultimately, we plan to expand our wood furnace line up. As you know we used to offer 3 sizes (small, medium, large), from my point of view I'm not convinced we need a bigger unit. With the Heat Commander already being a bit bigger than the Tundra and more efficient, I think we will be able to stretch the heating area compared to its predecessor. If you really want to fill it up, you can put up to 50 pounds of wood in it, which i'm pretty sure most of the time users don't fill the furnace to the maximum. Probably a few times a year it will happen, when it gets really cold you may need to fill it up to the baffle and recharge it more than usual, but overall it will produce enough heat to keep it comfortable for most of the house.

Most of us tend to buy bigger is better. From your perspective, do you think we should provide a unit larger or smaller than the Heat Commander?

Thanks,

Nicolas

Personally I think a smaller unit would be a more economical decision as these newer units are higher efficiency. A small medium and large epa2020 wood furnace I think would make the most sense as not everyone can afford a 4K diy furnace. I’m sold either way on the HC as the 10+ hour burn times are something of a dream for me at this point.

 

[Matt78]

Wondering why you are shutting the blower off prior to opening the door?

The newest software download actually does this. For me it helps get the fire going better on a colder start. And it doesn't suck ash out the fire box. Eric actually let me know of this software update

 

[Matt78]

Can the Field Controls barometric draft controller fit into a standard 6" stovepipe tee? I purchased the U

Where you place the probe and to what depth you place it in the stove pipe makes a difference on what you see for temps. In my experience, placing it within 12" of the collar and ON TOP of the pipe inserted so the probe tip sees at least the middle of the pipe makes for the most accurate (higher) temps. If you place it on the bottom, further down stream or not inserted far enough, you will be showing lower temps. I can drop my metered temps 50° by simply pulling the probe out maybe 0.5" to an 1".

Mines within 12" of the collar and probe is to center. Most of the time its at or just under 300 deg f.

 

[Matt78]

The newest software download actually does this. For me it helps get the fire going better on a colder start. And it doesn't suck ash out the fire box. Eric actually let me know of this software update

Sorry seen this was about a kuuma furnace. The HC shut the fan off on reload. Of course you gotta hit the green button!

 

[woodey]

No need to shut the blower off with my Kuuma, I leave the door open during the loading process and can open it at any point during the burn cycle without any smoke being released into the basement,