Everything Drolet Tundra - Heatmax...

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I hate ordering crap on the web. :)

Been pretty much solely buying online since the late 90's. I don't know how you can deal with the extreme lack of selection by limiting yourself to local retail. I'd go nuts trying to find what I want if I didn't do the majority of my non-food shopping online.

Like mentioned above, you need to have find the right specific gravity fluid.
 
Been pretty much solely buying online since the late 90's. I don't know how you can deal with the extreme lack of selection by limiting yourself to local retail. I'd go nuts trying to find what I want if I didn't do the majority of my non-food shopping online.

Like mentioned above, you need to have find the right specific gravity fluid.
Yeah I was hoping some wise guy on here would know the weight of the gauge oil and have a quick cheat. Ah well. I'll order it.
 
A while back we were talking about how nice it would be to have separate duct system for the wood furnace and tonight I just realized how big of a headache I have if I want to have both available at the same time.

I was sitting in the garage watching the furnace when all of a sudden the gas furnaces' blower kicked on. That makes no sense because the furnace is turned off. Apparently there is a mechanism that kicks the fan on based on the heat exchanger temp independent of the thermostat setting. Now, the ideal cure for this is to put a damper above the A coil but there is no room to do that. So it's either shut off the wood furnace when it gets really cold, or find a creative fix.

The blower on the gas furnace is drastically more powerful than the blower on the Tundra and there is no way the Tundra could overcome the force of the gas furnace blower so I'm thinking a solution could be to shut off the Tundra blower when the gas blower is on. Put a powered damper on both of the supply ducts which would open when the Tundra is calling for a blower, put a powered damper on the return side which opens when the gas furnace blower kicks on, and shut the tundra blower off when the gas blower is running. Air would travel backward through the Tundra when the backup blower was running but that doesn't matter as long as the motor is shut off, right?



How nice it would be to have separate ducts.

Now, I did buy a Quadra Fire 3100i for a song and it could be of some help but nothing compared to what the Tundra could do.
 
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Apparently there is a mechanism that kicks the fan on based on the heat exchanger temp independent of the thermostat setting
Yeah, the fan/limit switch.
Not sure I'm following the plan with the blowers and dampers...
I did buy a Quadra Fire 3100i for a song and it could be of some help but nothing compared to what the Tundra could do
You might be surprised...my lil Drolet 1400i (1.8 CF insert stove) will out heat the Tundra 2:1...but, that it only the main floor, and a load only lasts about half as long as in Tundra
 
I posted pics a while back of my ductwork and installation that might shed some light on my dilemna but for most of us, our installations are so specific to our wants/needs/installation/restrictions that in the end it's every man for himself. I'm trying to make a single set of duct work serve both the gas and wood furnaces. My setup is about the least ideal construction you could ask for. There is no practical way to add a second set of ductwork.

So the additional challenge with the insert is that it's in the basement. I plan to use the blower of the gas furnace to circulate the air but that requires installation of a new exterior door between the basement and garage. Every project requires a couple other projects. I had a smoke dragon in the same spot and it would heat the upstairs nicely if you could feed it every couple hours. Hopefully the Quadra Fire is more efficient. I was looking at the drolet 1800i but got the quadra fire for 1/3 the price
 
Air would travel backward through the Tundra

If your Tundra blower is spinning backward and the gas furnace kicks off and the Tundra kicks on, that might not be good. Also, since your gas blower is so much more volume/power than your Tundra blower, will the gas furnace blow your Tundra filter inside-out? I don't know how big of a concern those are, but on the other hand it's those kinds of details that can sink the whole thing.

One question--currently how often do the Tundra and gas furnace want to operate at the same time? Can you just put a powered diverter on top of the Tundra that simply dumps the Tundra's air straight into the basement during that 1% of the time they both want to operate?
 
If your Tundra blower is spinning backward and the gas furnace kicks off and the Tundra kicks on, that might not be good. Also, since your gas blower is so much more volume/power than your Tundra blower, will the gas furnace blow your Tundra filter inside-out? I don't know how big of a concern those are, but on the other hand it's those kinds of details that can sink the whole thing.

One question--currently how often do the Tundra and gas furnace want to operate at the same time? Can you just put a powered diverter on top of the Tundra that simply dumps the Tundra's air straight into the basement during that 1% of the time they both want to operate?

Great input. I'm not sure the blower is spinning backwards since it's not visible but it could very well be. I sure could add a third 8" powered damper that would be open when the Tundra calls for heat while the gas furnace is running but I'm not planning to at this point. That's a good idea though. Only down side is it's another $110 damper.

Here's what I'm planning, and I ordered the dampers an hour ago.

Powered damper in the return side of the gas furnace that will open any time the gas furnace blower is running (or better, close when the Tundra is running). Powered dampers in the two 8" Tundra supply side that will be open any time the Tundra is calling for blower and closed otherwise. A relay that will shut off the W line to the gas furnace any time the Tundra is calling for the blower. A relay that disables the Tundra blower any time the gas furnace blower is running.

If it's wired that way, the only time the conflict would cause any effect at all would be for the few seconds after the W line has been cut to the gas furnace, shutting the gas valve but leaving the blower running until the heat exchanger is cooled. During that 30 seconds or so, the gas furnaces' blower would run and would flow air backwards through the Tundra heat exchanger which is fine, as long as the heat is being removed.

I'm not sure about the filter blowing out, but if it did I could figure out something. Maybe leave one 8" round damper open or something.
 
Just make sure the Tundra dampers are powered closed, so if the power fails they will open allowing some gravity cooling of the firebox.
Also, what will keep the Tundra blower from being powered off while it is still burning if the house temp drops and the gas furnace kicks on?
 
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Just make sure the Tundra dampers are powered closed, so if the power fails they will open allowing some gravity cooling of the firebox.
Also, what will keep the Tundra blower from being powered off while it is still burning if the house temp drops and the gas furnace kicks on?

More good advice. Yes, the Honeywell dampers are set up as powered closed and they are industrial duty. I figure on replacing the motors and relays on a regular schedule- maybe every 5 years?. To the bigger question, yes the Tundra blower can be powered off while it has a blower call when the gas furnace is running. That would only happen when the gas furnace had been cut off and was relieving the residual heat in the heat exchanger. As soon as the heat exhanger has been cooled, which according to my brother, is about 30 seconds, the blower turns off and at that point the Tundra blower comes on. During that time the Tundra blower would be off, but air would be flowing across the heat exchanger from the gas furnace blower. Granted the air would be going backward through the heat exchanger but we aren't talking about an airplane. This heat exchanger isn't sophisticated and any airflow will remove the heat. If the gas furnace blower isn't sufficient to remove that heat, the factory snap disk would shut down the damper. From my observation, the gas furnace blower has many times the power of the tundra blower and it definitely draws more air over the Tundra heat exchanger than the factory blower does.

It's a work in progress to be sure.
 
I can't say there are any problems with it, just that I would get nervous in my own house with intentionally cutting power to the blower on a wood-burning appliance with a big fire. All the extra controls/relays make sense to ensure intended operation but then they also have a knack for causing unintended things to happen. At least that's my experience.

As you proceed, you might keep in the back of your mind how to design/build the system to make it easy to switch to plan B if either you or the insurance company want to.
 
More good advice. Yes, the Honeywell dampers are set up as powered closed and they are industrial duty. I figure on replacing the motors and relays on a regular schedule- maybe every 5 years?.
The motors on both of my Honeywell dampers died after two years due to heat. Their damper motor design is horrible. Essentially the motor has to be powered on all of the time ( the motor will get very hot after a while of being on ) to overcome the resistance of the return spring.

Instead of buying their crap again I found a guy on eBay who sold Belimo damper motors. It is a much better design. The gentleman that I worked with over the phone was very helpful too.
 
I have a topic about this unit open but I’m new here and maybe this is where all the discussion is held so here’s my post.

Hello everyone,

I am new to the forums but have been reading a bunch of post about the Drolet Tundra but haven’t seen an answer to my question yet. So here it is not going to bs anybody here I’m just looking for help/answers. I am considering buying a tundra unit however I have an unenclosed basement. Meaning I can see daylight and my duct work under the house. (Self explanatory I know sorry just want to make sure there’s no confusion) anyhow not going to drag this on but is there anyway that I could make a tundra work down there? I am mechanically inclined and a Do it yourselfer but I want to make sure I got a plan before I purchase this thing also what’s the best way to hook it up so it uses the housing duct work.

Thanks, for all the future help!
 
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I have a topic about this unit open but I’m new here and maybe this is where all the discussion is held so here’s my post.

Hello everyone,

I am new to the forums but have been reading a bunch of post about the Drolet Tundra but haven’t seen an answer to my question yet. So here it is not going to bs anybody here I’m just looking for help/answers. I am considering buying a tundra unit however I have an unenclosed basement. Meaning I can see daylight and my duct work under the house. (Self explanatory I know sorry just want to make sure there’s no confusion) anyhow not going to drag this on but is there anyway that I could make a tundra work down there? I am mechanically inclined and a Do it yourselfer but I want to make sure I got a plan before I purchase this thing also what’s the best way to hook it up so it uses the housing duct work.

Thanks, for all the future help!


I have a Tundra in the insulated basement of my house, and one in the office area of my work shop. There is a good deal of radiant heat off of the front of these units, heat that you can use if the furnace is installed in the conditioned area. In your case it sounds like that heat would be lost to the outdoors. The other area of concern would be your duct work itself. In your case it would have to be well insulated, or same deal, any losses from the duct work go right outside.

edit - all ducting should be insulated, meaning return and supply. The furnace itself has no insulation so there would be some losses there (sides and top) I would not even consider this type of install where I am located (Minnesota) but in a milder climate it may work. A picture of the area you would like to install it would help. Do you have existing chimney near by, do you have good access to bring wood to the furnace, etc.?
 
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The motors on both of my Honeywell dampers died after two years due to heat. Their damper motor design is horrible. Essentially the motor has to be powered on all of the time ( the motor will get very hot after a while of being on ) to overcome the resistance of the return spring.

Instead of buying their crap again I found a guy on eBay who sold Belimo damper motors. It is a much better design. The gentleman that I worked with over the phone was very helpful too.

Beat me to it. The link below is where I bought my whole custom made to my dimensions damper assembly from using a Belimo motor. The owner of the company told me right off the bat NOT to use a Honeywell motor.

The owner was extremely helpful in making sure I was getting what I wanted for my situation.

https://www.retrozone.com/

This is the guy I dealt with:
 
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I have a topic about this unit open but I’m new here and maybe this is where all the discussion is held so here’s my post.

Hello everyone,

I am new to the forums but have been reading a bunch of post about the Drolet Tundra but haven’t seen an answer to my question yet. So here it is not going to bs anybody here I’m just looking for help/answers. I am considering buying a tundra unit however I have an unenclosed basement. Meaning I can see daylight and my duct work under the house. (Self explanatory I know sorry just want to make sure there’s no confusion) anyhow not going to drag this on but is there anyway that I could make a tundra work down there? I am mechanically inclined and a Do it yourselfer but I want to make sure I got a plan before I purchase this thing also what’s the best way to hook it up so it uses the housing duct work.

Thanks, for all the future help!
Wow, that's a new one. How hard would it be to enclose this area?
Right off the bat it doesn't sound like a situation that would tend to lend itself to great success...but who knows, it you insulate the heck outta everything....maybe? As @3fordasho has mentioned above, there is a TON of radiant heat coming off these things...I'd guess 1/3 of the total heat to the house comes from just having thing "heating" the basement.
How big is your house? Is it well insulated?
 
Wow, that's a new one. How hard would it be to enclose this area?
Right off the bat it doesn't sound like a situation that would tend to lend itself to great success...but who knows, it you insulate the heck outta everything....maybe? As @3fordasho has mentioned above, there is a TON of radiant heat coming off these things...I'd guess 1/3 of the total heat to the house comes from just having thing "heating" the basement.
How big is your house? Is it well insulated?

It wouldn’t be extremely hard to close, But would take a little work. I will have to take a picture of the basement itself so you can get an idea. The house is a 2200 square ft ranch home. The insulation is mediocre since it was built in the 70s but has had some newer updates for insulation. However the basement is not very big, but big enough to house a tundra unit and wood for storage. The picture will tell, all it’s being used for storage now so it’s a tad messy but you’ll get an idea. There is a chimney from the fireplace that’s about 10-15 ft away I’ll post later tonight when I get off work. Thanks for the input everyone
 
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The owner of the company told me right off the bat NOT to use a Honeywell motor.

The owner was extremely helpful in making sure I was getting what I wanted for my situation.

https://www.retrozone.com/
Same place I got mine from. The owner seems like a good guy. He was super helpful, I wish more business owners were like that.
 
Same place I got mine from. The owner seems like a good guy. He was super helpful, I wish more business owners were like that.
Unfortunately it seems to be getting more uncommon to find a business that acts like they even want your business!
 
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Wow, that's a new one. How hard would it be to enclose this area?
Right off the bat it doesn't sound like a situation that would tend to lend itself to great success...but who knows, it you insulate the heck outta everything....maybe? As @3fordasho has mentioned above, there is a TON of radiant heat coming off these things...I'd guess 1/3 of the total heat to the house comes from just having thing "heating" the basement.
How big is your house? Is it well insulated?

Here is the pics I promised excuse the mess it’s a relatives stuff, soon to be removed. Do you see what I mean by open the top part of the brick is like 3 ft from the floor of the home
 

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@wwells48 I would NOT tie the wood furnace directly into flex duct. You are setting yourself up for a disaster. Wood furnaces should be tied into metal ducting for at the least the first 10 - 20 feet, preferably all duct work is metal. This is done in case the power goes out you. Flex duct can handle high temps but my guess is that it can do that when the air is moving is not stagnant like it is during a power outage.
 
This is done in case the power goes out you. Flex duct can handle high temps
Flex duct is only good for 200*...a wood furnace can hit that in a heartbeat if the power goes out right after a reload.
Yeah the only way that I would install a furnace down there would be if it was closed in and insulated.
 
Although, this is South Carolina and seeing as there's no insulation in the floor I wonder if the basement, even if "open", is as cold as we're used to. @brenndatomu is the man in my opinion, I just don't know enough to say it's a bad idea.
 
I just know how hard it was to get my Tundra to heat the house properly with an enclosed basement and a house that has decent insulation and air sealing. Although it doesn't get as cold in SC, I still think this install is gonna be a real challenge...but you are welcome to prove me wrong @wwells48 ==c (gotta document with pics and keep us updated though...;))
 
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I just know how hard it was to get my Tundra to heat the house properly with an enclosed basement and a house that has decent insulation and air sealing. Although it doesn't get as cold in SC, I still think this install is gonna be a real challenge...but you are welcome to prove me wrong @wwells48 ==c (gotta document with pics and keep us updated though...;))


That’s just the thing not sure if I want to make the investment. However somethings got to give, I am getting hit with 350 dollar gas bills. If this don’t pan out I’m looking at doing an insert with the fireplaces but not sure if the efficiency and output of heat would be worth the cost. The tundra looks like a very efficient unit that could output a lot of heat for my conditions. Just need some guidance here if it’s a go or no go. Thanks!
 
What do you have for a fireplace and chimney? What is the house layout? Our Drolet 1400i insert stove will out heat the Tundra hands down...BUT, since the firebox it is half the size, it is also half the burn time, AND it only heats the ground floor...floors get cold because the basement is cold, and it doesn't distribute the heat through the house as evenly as the furnace can/does...but a stove might possibly be a better option for you, dunno, need more info and/or some pics of your setup and floorplan/sq. footage to advise further...