New Furnace Day: Drolet Heat Commander

[usernametaken]

Hi everyone,

There are some points that we would like to address.

The specifications between the Heat Commander and its predecessor the Tundra/Heatmax:

The main reason the specs are pretty much the same is because we wanted to have a similar product. The size of the firebox is the same, but in fact if you measure each one you will find that Heat Commander one is a bit larger to incorporate a better brick pattern and improve production. So why is it the same? Because the two were not measured in the same way, some areas were considered to be part of the combustion chamber volume which were rejected at this time because we felt that the user should not be put wood there (Ex: the steel lip between the glass and the brick was considered part of the volume of the Heat Max, but we don't think it is a good idea to do this). Regarding the heating area, it has always been a debate here. How do you determine the right size of the heating area for a product? You can have the same house in a different climate zone which required a different heating input. The only way to properly size the furnace is to determine the heat input required for your home. Knowing the maximum heat output of the furnace (42,234 BTU / h delivered to the plenum and 47,052 BTU / h overall) and the heat input required to heat your home, you will be able to determine if the furnace is large enough or not. The maximum heat output is determined during a test where the thermostat is always calling for heat, therefore we do not recommend using this value. The furnace can achieve it but isn't designed to run at is maximum capacity all the time.

*** Important *** To select the correct size unit, you must use a value of approximately 30,000 to 35,000 btu at a baseline. Why do we recommend this? Because the furnace is not designed to burn at full capacity all day and if needed, you will have enough power for the colder days.

We are convinced that the Heat Commander can heat a larger home than its predecessor. If you are willing to load the furnace more frequently, it could probably heat up even more. The biggest gain over the Tundra / Heatmax is the smoother heat distribution throughout a burn. Automation makes it user-friendly and ensures better overall comfort and less babysitting. Another difference is that the Heat Commander uses a larger blower than the Tundra / Heatmax, which should help with a longer plenum in a larger house.

Software update

To be clear, we are not allowed to make any changes that will affect the emissions. Whether it's software or physical changes. After approval, all documentation and algorithm are forwarded to the EPA. We are also inspected at the factory to confirm that our products are still compliant. If we make any changes that could affect emissions performance, they must be submitted, approved or retested.

What’s coming next

There is always stress when you launch new technology in the field. We did extensive testing before bringing the HC to market, but it's still difficult to represent actual use. We are still heating units here and are in touch with users for their feedback.

Now that we have a few months of heating, we can say that we are quite happy with the performance of the Heat Commander. As some know, the Caddy range will be complemented by the Caddy Advanced. The new family member is expected to be in production during the summer. The Caddy Advanced will be an upgraded version of the Heat Commander for HVAC instead of DIY users.

COMING SOON
View attachment 274266




Nicolas

Great info Nicolas! Can you comment on the difference between the Caddy Advanced and the Caddy Advanced CR? Also, if you need anyone stateside to do some real world testing, I'm here for you...

 

[Boilers]

Great info Nicolas! Can you comment on the difference between the Caddy Advanced and the Caddy Advanced CR? Also, if you need anyone stateside to do some real world testing, I'm here for you...

@SBI_Nick
yes! Sign me up for Caddy testing or a HeatPro sized unit. I promise not to tinker with the code or anything like that.

 

[sloeffle]

@SBI_Nick
yes! Sign me up for Caddy testing or a HeatPro sized unit. I promise not to tinker with the code or anything like that.

I'd be a happy guinea pig too for Caddy testing too. And yes, I promise to not to tinker with the furnace.

 

[trx250r87]

I woke up to -13 degrees F outside temperature this morning, not sure what the wind-chill was. At 6am, 8 hours after loading the furnace, the house was at 70 degrees and Heat Commander blower was still delivering heat to the house. I reloaded on minimal hot coals and the house temperature started climbing within 20 minutes to 71 degrees.

I really noticed a difference when I lowered the included thermostat temp by 1 degree. The HC burns are longer and even more even, consistent heat is delivered!

9 times out of 10 the house is at 70 degrees when I wake up.

Eric

 

[brenndatomu]

I really noticed a difference when I lowered the included thermostat temp by 1 degree. The HC burns are longer and even more even, consistent heat is delivered!

Not following you here? You literally lowered the Tstat 1*...how's that help?
I've always thought that old school wood furnaces (simple open/closed style air control) could benefit from a Tstat with really tight hysteresis, like 0.1*, or something like that...no long runs of low burn, or high burn...

 

[trx250r87]

Not following you here? You literally lowered the Tstat 1*...how's that help?
I've always thought that old school wood furnaces (simple open/closed style air control) could benefit from a Tstat with really tight hysteresis, like 0.1*, or something like that...no long runs of low burn, or high burn...

Y
Yes, literally lowered it 1 degree, from 71 to 70. This must be a sweet spot for my setup. It caused the furnace to enter "energy saving" mode earlier in the burn and stay there longer. While in this mode the intake air is reduced and the blower fan cycles on/off every few minutes as the plenum temps cycle.

Keep in mind I installed the dedicated thermostat that is included with the HC about 10' away, at the bottom of my basement stairs.

Eric

 

[JRHAWK9]

I woke up to -13 degrees F outside temperature this morning, not sure what the wind-chill was. At 6am, 8 hours after loading the furnace, the house was at 70 degrees and Heat Commander blower was still delivering heat to the house. I reloaded on minimal hot coals and the house temperature started climbing within 20 minutes to 71 degrees.

I really noticed a difference when I lowered the included thermostat temp by 1 degree. The HC burns are longer and even more even, consistent heat is delivered!

9 times out of 10 the house is at 70 degrees when I wake up.

Eric

You are in the same cold snap we are in. Six nights in a row of double digit below zero lows/single digit daytime highs and we are about half way through. -14° here this morning. We are in a low lying area and it always seems to get colder here than the forecast. The automated coal burn down on those HC's would be a great feature to have when one needs it, like during these cold snaps. Is there a way to disable it though? 98% of the time most people would not need it and it would not benefit them when it's not very cold. Some of us, outside of these cold temps, actually do things to prolong coals in order to reduce the BTU/hr output of the unit when the heat is not needed in order to not overheat the house. Also to maintain the embers as long as possible in order to help facilitate a re-light later on when it's time to do so. Just curious, as it would be very handy to have for the handful of times it would be beneficial, but would be nice to be able to disable it for the majority of the time it's not needed or wanted.

 

[trx250r87]

You are in the same cold snap we are in. Six nights in a row of double digit below zero lows/single digit daytime highs and we are about half way through. -14° here this morning. We are in a low lying area and it always seems to get colder here than the forecast. The automated coal burn down on those HC's would be a great feature to have when one needs it, like during these cold snaps. Is there a way to disable it though? 98% of the time most people would not need it and it would not benefit them when it's not very cold. Some of us, outside of these cold temps, actually do things to prolong coals in order to reduce the BTU/hr output of the unit when the heat is not needed in order to not overheat the house. Also to maintain the embers as long as possible in order to help facilitate a re-light later on when it's time to do so. Just curious, as it would be very handy to have for the handful of times it would be beneficial, but would be nice to be able to disable it for the majority of the time it's not needed or wanted.

There is no option to prolong coals unfortunately. That is about the ONLY thing I miss about the Tundra. It has taken some time to get used to this but I'm getting better at judging how long I have until I need to reload.

Eric

 

[SBI_Nick]

There is no option to prolong coals unfortunately. That is about the ONLY thing I miss about the Tundra. It has taken some time to get used to this but I'm getting better at judging how long I have until I need to reload.

Eric

You can't disable it, but as long as you don't have a call for for heat it will stay closed.

 

[JRHAWK9]

You can't disable it, but as long as you don't have a call for for heat it will stay closed.

That would work.

 

[andym]

Hi everyone,

There are some points that we would like to address.

The specifications between the Heat Commander and its predecessor the Tundra/Heatmax:

The main reason the specs are pretty much the same is because we wanted to have a similar product. The size of the firebox is the same, but in fact if you measure each one you will find that Heat Commander one is a bit larger to incorporate a better brick pattern and improve production. So why is it the same? Because the two were not measured in the same way, some areas were considered to be part of the combustion chamber volume which were rejected at this time because we felt that the user should not be put wood there (Ex: the steel lip between the glass and the brick was considered part of the volume of the Heat Max, but we don't think it is a good idea to do this). Regarding the heating area, it has always been a debate here. How do you determine the right size of the heating area for a product? You can have the same house in a different climate zone which required a different heating input. The only way to properly size the furnace is to determine the heat input required for your home. Knowing the maximum heat output of the furnace (42,234 BTU / h delivered to the plenum and 47,052 BTU / h overall) and the heat input required to heat your home, you will be able to determine if the furnace is large enough or not. The maximum heat output is determined during a test where the thermostat is always calling for heat, therefore we do not recommend using this value. The furnace can achieve it but isn't designed to run at is maximum capacity all the time.

*** Important *** To select the correct size unit, you must use a value of approximately 30,000 to 35,000 btu at a baseline. Why do we recommend this? Because the furnace is not designed to burn at full capacity all day and if needed, you will have enough power for the colder days.

We are convinced that the Heat Commander can heat a larger home than its predecessor. If you are willing to load the furnace more frequently, it could probably heat up even more. The biggest gain over the Tundra / Heatmax is the smoother heat distribution throughout a burn. Automation makes it user-friendly and ensures better overall comfort and less babysitting. Another difference is that the Heat Commander uses a larger blower than the Tundra / Heatmax, which should help with a longer plenum in a larger house.

Software update

To be clear, we are not allowed to make any changes that will affect the emissions. Whether it's software or physical changes. After approval, all documentation and algorithm are forwarded to the EPA. We are also inspected at the factory to confirm that our products are still compliant. If we make any changes that could affect emissions performance, they must be submitted, approved or retested.

What’s coming next

There is always stress when you launch new technology in the field. We did extensive testing before bringing the HC to market, but it's still difficult to represent actual use. We are still heating units here and are in touch with users for their feedback.

Now that we have a few months of heating, we can say that we are quite happy with the performance of the Heat Commander. As some know, the Caddy range will be complemented by the Caddy Advanced. The new family member is expected to be in production during the summer. The Caddy Advanced will be an upgraded version of the Heat Commander for HVAC instead of DIY u
Nicolas

Very helpful information.

 

[FixedGearFlyer]

Prepare yourself! This video is a riveting 20 minutes of watching the Heat Commander establish a fire from a cold start.

SBI asked me for details of our cold start process and I thought I'd post it here, too. The key points are below and the summary is that it takes less than 20 minutes for the Heat Commander to establish a nice, efficient secondary burn on a cold start with a full firebox of wood.

• The match is lit around 30 seconds.
• 6:00 - the door is closed and latched.
• 9:45 - Heat Commander closes down the air supply.
• 12:00 - Heat Commander opens the air supply.
• 13:45 - Heat Commander closes the air supply for the 2nd time.
• 17:23 - Heat Commander opens the air supply.
• 18:50 - Heat Commander closes the air supply for the third and last time. An efficient, clean secondary burn is nicely established.

The four things I did were load the firebox, light the kindling, press the load/reload button, and close and latch the door, all of which are done in the first 6 minutes. Everything else is managed by the furnace.

For reference, the box is filled with wrist-sized, soft maple splits that are all below 15% M.C., the kindling is bone-dry white cedar split pencil-thin, and the two knotted pieces of newspaper help get the draft going quickly.

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[trx250r87]

Prepare yourself! This video is a riveting 20 minutes of watching the Heat Commander establish a fire from a cold start.

SBI asked me for details of our cold start process and I thought I'd post it here, too. The key points are below and the summary is that it takes less than 20 minutes for the Heat Commander to establish a nice, efficient secondary burn on a cold start with a full firebox of wood.

• The match is lit around 30 seconds.
• 6:00 - the door is closed and latched.
• 9:45 - Heat Commander closes down the air supply.
• 12:00 - Heat Commander opens the air supply.
• 13:45 - Heat Commander closes the air supply for the 2nd time.
• 17:23 - Heat Commander opens the air supply.
• 18:50 - Heat Commander closes the air supply for the third and last time. An efficient, clean secondary burn is nicely established.

The four things I did were load the firebox, light the kindling, press the load/reload button, and close and latch the door, all of which are done in the first 6 minutes. Everything else is managed by the furnace.

For reference, the box is filled with wrist-sized, soft maple splits that are all below 15% M.C., the kindling is bone-dry white cedar split pencil-thin, and the two knotted pieces of newspaper help get the draft going quickly.

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For more detailed information, see our cookies page.

Accept third party cookies

Great video! It's always nice to see other peoples methods. I have not tried the vertical kindling trick and I don't think I have had flames that blue/purple with mine, or is that just how your camera picks up the flame? I also mainly burn red oak vs maple and don't leave my door cracked for that long.

What was the outside temperature, what was your draft set at and how long until you had to reload?

Eric

 

[brenndatomu]

Prepare yourself! This video is a riveting 20 minutes of watching the Heat Commander establish a fire from a cold start.

SBI asked me for details of our cold start process and I thought I'd post it here, too. The key points are below and the summary is that it takes less than 20 minutes for the Heat Commander to establish a nice, efficient secondary burn on a cold start with a full firebox of wood.

• The match is lit around 30 seconds.
• 6:00 - the door is closed and latched.
• 9:45 - Heat Commander closes down the air supply.
• 12:00 - Heat Commander opens the air supply.
• 13:45 - Heat Commander closes the air supply for the 2nd time.
• 17:23 - Heat Commander opens the air supply.
• 18:50 - Heat Commander closes the air supply for the third and last time. An efficient, clean secondary burn is nicely established.

The four things I did were load the firebox, light the kindling, press the load/reload button, and close and latch the door, all of which are done in the first 6 minutes. Everything else is managed by the furnace.

For reference, the box is filled with wrist-sized, soft maple splits that are all below 15% M.C., the kindling is bone-dry white cedar split pencil-thin, and the two knotted pieces of newspaper help get the draft going quickly.

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Is that real time video? Flames look awful "fast"...

 

[FixedGearFlyer]

Great video! It's always nice to see other peoples methods. I have not tried the vertical kindling trick and I don't think I have had flames that blue/purple with mine, or is that just how your camera picks up the flame? I also mainly burn red oak vs maple and don't leave my door cracked for that long.

What was the outside temperature, what was your draft set at and how long until you had to reload?

Eric

We have to leave the door cracked that long with this method to ensure that the primary logs are properly charred and engaged. It's cheating and not the best method - it would be better to light a cold furnace with a smaller load and a top down fire, but this works and is less time in the end. That kindling is BONE DRY cedar, so we don't need the paper to light it - you just touch it with a match and it goes. The paper helps get the draft going more quickly, though.

I think the camera is just picking up a strange color balance and knocking down the exposure some.

The outside temp was -6*F, light North wind, draft is controlled with a baro at a max of 0.06" W.C., and we'll reload after about 12 hours.In this weather, we've been loading around 9:00am and 9:00pm with a full firebox each time.

 

[FixedGearFlyer]

Is that real time video? Flames look awful "fast"...

It is, but even though it's at 1x speed, it looks fast on camera for some reason.

 

[andym]

What would the exhaust temp have been at end of video? What would it have peaked at during the video?

 

[FixedGearFlyer]

What would the exhaust temp have been at end of video? What would it have peaked at during the video?

During the video, I'm note sure. It was early in the burn.

Typically, we see temps on the heat exchanger door of about 300-325*F and flue pipe temps around 250-275*F when the furnace is cruising at mid-burn. That's a single wall pipe with thermometer mounted about 4 inches after the furnace collar.

I paid a lot closer attention to those numbers with the Tundra I because we had control of the damper. I don't pay as much attention now, since the HC is doing the work and it was doing a splendid job of managing it all when I was number-peeping in the beginning.

Also, it's at about 10 hours and we just hit the heavy coaling stage. We're on target for a 9pm hot reload and we've been at 70*F with single digits and a North wind all day on that one load.

 

[FixedGearFlyer]

What would the exhaust temp have been at end of video? What would it have peaked at during the video?

In the heavy coaling stage right now, we're at 250*F on the heat exchanger door and 180-ish on the flue pipe.

 

[andym]

Probably similar numbers to what I'm seeing then (HMX2). My temp control limits it at 640 (internal) during start up. It cruises starting at 350 down to 250 or 260.
But that coal bed is no comparison. That is impressive.

 

[JRHAWK9]

Also, it's at about 10 hours and we just hit the heavy coaling stage. We're on target for a 9pm hot reload and we've been at 70*F with single digits and a North wind all day on that one load.

What's really impressive to me is your home's heatload! A full firebox in your HC is probably around 50-60 lbs of oak (even less if you use ash or other less dense wood), seeing it's a bit smaller firebox than my Kuuma. Using 6,500BTU's/LB of wood, and assuming 55lbs per load, you are putting into your house an average of around 30,000 BTU's/hr GROSS over a day. You need to take in account furnace efficiency yet off of that number.....so more realistically around 23,000 BTU's per hour average over a day. Like I said, even less if you are burning ash, elm, etc. Granted I'm keeping our home a bit warmer, but I go through pretty much double what you are heating our pig of a place in these double digit below zero nights and low single digit highs. We also used to use 1,300 gallons of LP a year though too keeping just the upstairs 68°.

These have been our high/low's over the past 7 days, not counting today yet. Today's high was -1° though, supposed to get down to -15° tonight.

Anyway, I'm jealous of your heatload in these temps.

 

[JRHAWK9]

In the heavy coaling stage right now, we're at 250*F on the heat exchanger door and 180-ish on the flue pipe.

View attachment 274475

This appears to be a magnetic gauge? If so, you really should have a probe type for measuring internal flue temp of the gasses. Internal flue gasses are typically double that of what the external pipe measures on it's surface like that.

 

[FixedGearFlyer]

This appears to be a magnetic gauge? If so, you really should have a probe type for measuring internal flue temp of the gasses. Internal flue gasses are typically double that of what the external pipe measures on it's surface like that.

Agreed. There just isn't much reason for me to put one in on this furnace - there's a flue gas temp probe connected to the SBI data pack and I can't adjust anything that would affect it, anyway. Me reading the flue temps is just for a general baseline of performance, not for actual management of the burn.

 

[FixedGearFlyer]

What's really impressive to me is your home's heatload! A full firebox in your HC is probably around 50-60 lbs of oak (even less if you use ash or other less dense wood), seeing it's a bit smaller firebox than my Kuuma. Using 6,500BTU's/LB of wood, and assuming 55lbs per load, you are putting into your house an average of around 30,000 BTU's/hr GROSS over a day. You need to take in account furnace efficiency yet off of that number.....so more realistically around 23,000 BTU's per hour average over a day. Like I said, even less if you are burning ash, elm, etc. Granted I'm keeping our home a bit warmer, but I go through pretty much double what you are heating our pig of a place in these double digit below zero nights and low single digit highs. We also used to use 1,300 gallons of LP a year though too keeping just the upstairs 68°.

These have been our high/low's over the past 7 days, not counting today yet. Today's high was -1° though, supposed to get down to -15° tonight.

View attachment 274479

Anyway, I'm jealous of your heatload in these temps.

We're exclusively burning red maple.

Our house is a 32x32 rennovated one-room schoolhouse. We completely stripped and rebuilt the second floor with doubled, offset studs for a thermal break and had high-R blown in insulation put in both the walls and ceiling. It's so efficient up there that we usually keep the second floor duct run closed off or it gets too warm to sleep.

The block basement is insulated with foam board on the walls and both sealed foam (as a vapor barrier) and batts on the rim joists. The basement sits around 58 to 60*F from the radiant heat off the furnace, plus I added two registers with the Heat Commander so we can warm it up more, if we want.

The first floor is a mixed bag. We've redone all of the windows and the North and East walls. The West and South walls, however, are still loose-bead poured styrofoam insulation and a cold South wind is really rough for us.

The HC is a total game changer, though. The temp swings through various burn phases are gone and the amount of wood we're using on these cold, two-load days is about 30% less.

Our actual wood reduction for the season will be impossible to pin down because we put in a pellet stove on a thermostat on the main floor for those low-load shoulder season days and the warmer Winter overnights when an evening load in the furnace would be too much but we don't want to wake up to a 50*F first floor.

We literally put in the pellet stove a week before the Heat Commander became an option for us through the SBI connected furnace data gathering program.

All told, we averaged 5 full cords for the 6 years we had the Tundra and no pellet stove. We put 4.5 seasoned cords in the basement in late October . . . And have only burned 1.25 so far. I'll be surprised if we use even half the wood that we used to burn between the HC and the PP130.

 

[JRHAWK9]

I'll be surprised if we use even half the wood that we used to burn between the HC and the PP130.

If the HC does better at even heating you should be able to use that solely instead of burning $$ by paying for pellets. Last time I checked, pellets are $$$ than using LP. With the more even heat throughout the burn you should be able to manage the shoulder seasons with the HC. I know Kuuma also has a nice even heat output and is pretty easy to manage during the shoulder seasons by just loading the correct amount of wood.