Tiny Wood Stove In a Tiny House - Confirming Issues

[OffGridTinyHome]

Hello,

This is my first time posting in here. I browsed the forums for a bit and found lots of answers to confirm that indeed I have some issues with my wood stove, and that MOST of my guesses on what I need to do are correct. What I am looking for is confirmation.... "If its worth doing, its worth doing right" kinda thinking... im about to pay for not doing things right the first time and I sure as heck want to make sure I do the overhaul right this time.

Ok, so lets brief you on the situation! I designed and built an off-grid tiny house. Our primary heating system is a cubic mini-wood stove, the grizzly model. Here is a link to details and specs:
(broken link removed to https://cubicminiwoodstoves.com/collections/grizzly-cb-1210/products/cb-1210-br-cubic-mini-wood-stove)

I have been burning the wood stove for 7 months, but really only have started using it in the past ~month as temperatures have dropped here in Alberta, Canada. (its -20C out at night... -4F).

I am having several issues and think I know what to do... lets see what you gents and gals think... Here is a pic and the issues:

Issue #1: I am having condensation/water drip down the pipe both when the stove is running (more) and also when it is not running (less). The dripping is obviously happening on the outside of the pipe as you can see (seems to be dripping from the rain cap and hitting the pipe.) What you dont see in this pic is that this dripping is becoming an issue inside the house! Brown water is dripping in from the connection spots and the metal tape is not able to seal it.

• I haven't ruled out that the wood is the right moisture level, but im burning birch that was sheltered for 2 years and pallet wood for kindling, so Im thinking this is not the primary issue. That the stove pipe is dripping when we haven't run the stove that day is confirmation of this.
• I know I need to have the male end of the pipes always facing down, which I do where I can. I say "where I can" because the elbows require male ends on both sides. So as the pipe goes horizontal to go inside the house the male ends are facing the "wrong" way - Which brings me to my first question - 1) How do I stop water in this situation where the orientation alone seems to be impossible to design water against as there has to be connections. And how do you orient male connection correctly with elbows?? Here is an image of the drips at their worst:
• 

That's a lot of condensation right?! I literally have a bread pan to catch the drip and have to empty it every few days and in this pic above (happened this bad yesterday for the 1st time thus why I'm reaching out for help) we actually had another drip creeping out from the connection where where the pipe meets the stove (drip 3). Which is a huge concern because that will be hard to fix.... my plumber blow torched that pipe end to make it expand, just so it would fit on to the end of the stove, it is VERY snug and wont be easy to take off... but as we all can see, it is a classic example of the male connection going UP into the pipe, instead of a pipe going down into the stove connection. So I think its safe to presume that should any water ever come down the pipe it will try to get out at this joint. Which brings me to question #2 - What are your guys opinions on what to do at drip 3 location if anything?

Alright so I have outlined a lot of things, im sure you have lots of thoughts, but hear out this last variable which im guessing is one of the largest issues. When I bought this stove, they only sold single wall flu pipe. Its 3".... which apparently is a specialty product as not a single store in my area sells 3", let alone double wall 3".

Low and behold NOW the company I bought this stove (and the single wall flu pipe) sells double wall 3" pipe. Here is the new product:
https://cubicminiwoodstoves.com/col...4-ss-24-stainless-steel-double-wall-flue-pipe

I couldnt help but notice they now no longer sell elbows, and they also include in the fine print on this new product "We suggest to exit straight up and out the roof. For that reason, we do not have elbows for our flue pipes." So now im feeling a bit hooped... I cant really change the design of the flu system now. My best guess to help myself is this:

Buy the double wall flu pipe from the company above anyways... try to find new/better elbows that fits the double wall flu... somewhere....

Then connect the double wall to the single wall flu pipe as it exits the house (that could be an interesting connection). Where the elbow is that goes from horizontal back to vertical, what are your thoughts on having a T connection so that water coming down the stove can be captured here??? Not sure if such a product exists but it would be easier to have a water trap here.

Alright, thats all I got. If you can help answer the 2 questions, and give me your suggestions for redesigning the flu system that would be greatly appreciated... I look forward to hearing your ideas before I order the expensive double wall 3" flu sections.

Thanks in advance,

K

 

[webby3650]

I don’t have experience with your tiny stove. Galvanized pipe is not what you should be using for the flue though. I’m also confused as to why your elbows are crimped in both ends, like other warm air pipe, it has a make and a female end.

What pipe does the manufacturer recommend using?

 

[OffGridTinyHome]

I don’t have experience with your tiny stove. Galvanized pipe is not what you should be using for the flue though. I’m also confused as to why your elbows are crimped in both ends, like other warm air pipe, it has a make and a female end.

What pipe does the manufacturer recommend using?

Hi Webby,

The pipe I have was the pipe the manufacturer sold off their website with the stove, so it was what they recommended. The pipe I linked in my 1st message is what they apparently recommend now.

The elbows I have now are the ones they used to sell and they no longer sell them. The elbows are not crimped on either side, you stick the crimped male end of the flu pipe into both ends of the elbow, thus one end will face the wrong direction to discourage water getting outside the pipe.

I too am confused why the elbows had 2 female ends, but at the time of install, I didnt know any better and my plumber who had experience installing wood stoves did not mention anything.

 

[webby3650]

Hi Webby,

The pipe I have was the pipe the manufacturer sold off their website with the stove, so it was what they recommended. The pipe I linked in my 1st message is what they apparently recommend now.

The elbows I have now are the ones they used to sell and they no longer sell them. The elbows are not crimped on either side, you stick the crimped male end of the flu pipe into both ends of the elbow, thus one end will face the wrong direction to discourage water getting outside the pipe.

I too am confused why the elbows had 2 female ends, but at the time of install, I didnt know any better and my plumber who had experience installing wood stoves did not mention anything.

Well, if he had much experience he would have known better. He also would have mentioned the health concerns with galvanized steel offgassing.

 

[electrathon]

I am figuring that you will soon get a poo storm for what you did here. Many reasons for this, some valid, some so, so.

What I would do in your situation... Not saying this is legal or code. You are neither now, but you are also very unsafe currently. Two options. One is to get chimney pipe for a boat wood stove. This is the best option, very expensive. I am going to assume you are not going to go that direction. That said, go to an exhaust shop and buy 3" exhaust pipe. Weld your seams. Solid chimney. It will last for years. If you burn wet wood you will have creosote buildup issues. The pipe you have is too big for your stove. the large pipe will make draft issues. It should be matched to your stove.

You have ventilation/moisture issues in your house causing the dripping. This is a separate issue than the fire hazard you currently have. The moist air in your house is being drawn up the cold chimney, condensing and dripping back inside.

 

[Doc C]

It seems you have a conundrum.....the proper way would be too find new pipe that is made for wood stoves. I think the people that sold your stove and pipe did not know at the time what they were doing.

I would not want to live in a tiny home with that much heat going through galvanized pipe.

There is an old saying that everything is poisonous and nothing is poisonous, it’s the dose that determines what is poison.

Being in that small of an area with galvanized pipe off gassing can’t be healthy. Maybe there is a point where galvanized pipe becomes safe when heated but I am not 100% sure on that.

Slight fire hazard with creosote dripping down the pipe.

I am not sure how you can make what you have safe and usable and without issues.

Also I beleive that the condensation issue will go away when you get rid of the galvanized pipe.

My vote would be to replace all of it and go straight out the roof is that is an option even if it means more work.

And I don’t have a solution to repair what you have.

 

[OffGridTinyHome]

I just double checked my order from the company and it is stainless steel, not galvanized.

Thanks for your advice Electrathon and Doc C. I crack the nearby window when running the fire, but it is still possible that moisture from inside the house is going up the chimney when burning. I had also installed that dampener seen in the pics and would close both it and the air intake for the stove to stop air leaving the house (and causing condensation), but its possible the air still is going that way and thus the drip issue even when we arent running the stove.

Electrathon - The pipe is 3" and that is the size it is supposed to have.

I could look into trying to go straight up through the roof but that would be quite a redesign. Im not sure how that would fix the moisture though...

 

[Doc C]

I just double checked my order from the company and it is stainless steel, not galvanized.

Thanks for your advice Electrathon and Doc C. I crack the nearby window when running the fire, but it is still possible that moisture from inside the house is going up the chimney when burning. I had also installed that dampener seen in the pics and would close both it and the air intake for the stove to stop air leaving the house (and causing condensation), but its possible the air still is going that way and thus the drip issue even when we arent running the stove.

Electrathon - The pipe is 3" and that is the size it is supposed to have.

I could look into trying to go straight up through the roof but that would be quite a redesign. Im not sure how that would fix the moisture though...

Wood stoves naturally make a house have less humidity. I would think a tiny house would dry out faster.

Do you have access to a humidity gauge you can set up in your house for a little bit and let us know.

I wondering if it’s moisture from within the wood or within the house

 

[OffGridTinyHome]

Good idea. I have an Ecobee thermostat with a humidity indicator. Its at 47% right now and we have been running the wood stove all morning. (fire just finished dying out). Ill keep an eye on it in the next couple days and report back. We also do have an HRV called a Lunos Ego2 which is constantly moving air in and out of the house.

 

[bholler]

What you have is not chimney pipe it is uninsulated which means it will cool quickly and creat massive ammouts of creosote. Call the company and demand your money back and get a real chimney system from someone who knows what they are doing. I am sorry to be so blunt but who ever sold you that as a chimney should be put out of buisness it is rediculous.

 

[Doc C]

Good idea. I have an Ecobee thermostat with a humidity indicator. Its at 47% right now and we have been running the wood stove all morning. (fire just finished dying out). Ill keep an eye on it in the next couple days and report back. We also do have an HRV called a Lunos Ego2 which is constantly moving air in and out of the house.

Humidity is around where i consider normal for heating with wood.

Is the condensation coming from inside the pipe or is it forming on the outside of the pipe?

Bholler brought up a good point. I’m pretty sure a few phone calls are in order. The people that sold you that pipe should be shot.

 

[bholler]

Humidity is around where i consider normal for heating with wood.

Is the condensation coming from inside the pipe or is it forming on the outside of the pipe?

Bholler brought up a good point. I’m pretty sure a few phone calls are in order. The people that sold you that pipe should be shot.

I am currently trying to figure out who to report them to in canada.

 

[Doc C]

I am currently trying to figure out who to report them to in canada.

That’s a bad deal. My guess is the stove company jumped on the tiny house bandwagon and knew nothing about wood stoves, found some random parts, and threw them into a kit and called it good. Not cool

 

[bholler]

That’s a bad deal. My guess is the stove company jumped on the tiny house bandwagon and knew nothing about wood stoves, found some random parts, and threw them into a kit and called it good. Not cool

No it really isnt. I have seen some really scary stuff dont by tiny house guys. There are 3 companies here that build them and 2 of them do some really scary stuff for heating.

 

[electrathon]

I was at a tiny house show this morning (in Portland Oregon) and there was a guy there selling Salamander stoves (tinystoves.shop) telling people they are legal to install. I asked a few questions and he sort of said they are legal in the EU so that makes them legal in the USA too sense their standards are stricter than ours and to not worry about the local codes because they do not matter. He was using a few of the code words that are like loopholes when you press for better answers. It sounds similar to what happened to this guy.

The moisture inside the pipe is being drawn out of the home and into the pipe, condensing and dripping back in. I am guessing this is happening when the stove is off. Trailers and small spaces are notorious for moisture issues. 47% humidity sounds high to me if it is below freezing outside. I have seen 2" of ice buildup inside of a poorly insulated/vapor barriered wall up in Alaska in the winter time. Humidity can cause a lot of issues in a house in cold climates. Cooking, bathing, breathing all add to the problem.

 

[Doc C]

I was at a tiny house show this morning (in Portland Oregon) and there was a guy there selling Salamander stoves (tinystoves.shop) telling people they are legal to install. I asked a few questions and he sort of said they are legal in the EU so that makes them legal in the USA too sense their standards are stricter than ours and to not worry about the local codes because they do not matter. He was using a few of the code words that are like loopholes when you press for better answers. It sounds similar to what happened to this guy.

The moisture inside the pipe is being drawn out of the home and into the pipe, condensing and dripping back in. I am guessing this is happening when the stove is off. Trailers and small spaces are notorious for moisture issues. 47% humidity sounds high to me if it is below freezing outside. I have seen 2" of ice buildup inside of a poorly insulated/vapor barriered wall up in Alaska in the winter time. Humidity can cause a lot of issues in a house in cold climates. Cooking, bathing, breathing all add to the problem.

My humidity sits right at 40% in my 1960 square foot house. Kind of figured 47% would be about normal for a tiny house. Also with his HRV I have a feeling that his humidity is influenced more by outside air then most of us.

 

[electrathon]

My humidity sits right at 40% in my 1960 square foot house. Kind of figured 47% would be about normal for a tiny house. Also with his HRV I have a feeling that his humidity is influenced more by outside air then most of us.

It really depends on outside temp. If it is 10 degrees outside then humidity is almost nil, it is all frozen. At 35 degrees you will have a lot of humidity. It took me a long time to get used to this change when I moved from Alaska to Oregon.

 

[Doc C]

I think the answer to almost all of these problems is the proper pipe that allows creosote and moisture to follow the proper path.

As far as the condensation fix maybe running bath fan more often and trying to get the humidity to drop.

I see a water kettle on the stove. If you are adding humidity on purpose with this I would probably try not keeping water in it.

Maybe target less then 40% after you replace the pipe and see if that helps. Go to low and you'll be dealing with static and dry nose and throat and stuff some there is a balance to be found.

 

[Hogwildz]

I just skimmed through the posts, sorry if this was touched on, but by the looks of the creosote running down the piping, I would guess to say the pipe is run backwards. When properly run, any dripping happens inside the pipe running down & into the stove, rather than out each joint.

If you can manage to run the pipe up through the roof, you will suffer less condensation as the pipe will be in conditioned space and not as cold to cause the condensation.

Properly run piping, with correct pipe, should not need tape of any kind. That tape will do nothing, and the tape above the stove is not going to last very long.

Out of curiosity, can you share photos of the rest of the house.

 

[SuperJ]

Wow, that's a tiny stove. You don't really get how small it is until you see the guys holding it on their website.

I agree with Hogwildz, if the fittings are properly orientated (so the female openings point up and the male down towards the stove), any condensation or liquid creosote should stay in the pipe.

How are you controlling the fire? If you are closing that damper above the stove you will probably create even more problems.

A couple observations not necessarily related to the root of your creosote dripping problem.

• That inside slide damper above the stove looks like it might not be appropriate
• the pipe looks stainless, but it doesn't seem like a good replacement for a outside class A chimney. But to go that small your in uncharted waters.
• Hard to tell, but it looks like your upper sections of pipe need another support above the roof line.

 

[SuperJ]

The instructions for the pipe on their website is suspect. Looks upside down.
https://cubicminiwoodstoves.com/col...4-ss-24-stainless-steel-double-wall-flue-pipe

 

[OffGridTinyHome]

I think the answer to almost all of these problems is the proper pipe that allows creosote and moisture to follow the proper path.

As far as the condensation fix maybe running bath fan more often and trying to get the humidity to drop.

I see a water kettle on the stove. If you are adding humidity on purpose with this I would probably try not keeping water in it.

Maybe target less then 40% after you replace the pipe and see if that helps. Go to low and you'll be dealing with static and dry nose and throat and stuff some there is a balance to be found.

I have been watching the moisture since I posted this thread and it fluctuates between 40%-55% depending on what we are doing in the house. I have the ability to control the HRVs rate of air exchange so I will start managing the moisture more with that system. Im wondering if a de-humidifier is also in order...

And thanks for the tip re the kettle. Indeed I bought it because someone told me I might need to ADD moisture to the air haha. Honestly, I never fill the darn thing as it boils off quickly. I will be sure to get rid of it now as its seemingly going to be purely decoration

 

[OffGridTinyHome]

I just skimmed through the posts, sorry if this was touched on, but by the looks of the creosote running down the piping, I would guess to say the pipe is run backwards. When properly run, any dripping happens inside the pipe running down & into the stove, rather than out each joint.

If you can manage to run the pipe up through the roof, you will suffer less condensation as the pipe will be in conditioned space and not as cold to cause the condensation.

Properly run piping, with correct pipe, should not need tape of any kind. That tape will do nothing, and the tape above the stove is not going to last very long.

Out of curiosity, can you share photos of the rest of the house.

Sure! We havent done a share with the larger tiny house community yet but have showed the house off at the Edmonton Home and Garden show.

We did share some of our story designing and building the house at Edmontontiny.wordpress.com but we havent written on there in a while. Lifes been busy!

 

[OffGridTinyHome]

Wow, that's a tiny stove. You don't really get how small it is until you see the guys holding it on their website.

I agree with Hogwildz, if the fittings are properly orientated (so the female openings point up and the male down towards the stove), any condensation or liquid creosote should stay in the pipe.

How are you controlling the fire? If you are closing that damper above the stove you will probably create even more problems.

A couple observations not necessarily related to the root of your creosote dripping problem.

• That inside slide damper above the stove looks like it might not be appropriate
• the pipe looks stainless, but it doesn't seem like a good replacement for a outside class A chimney. But to go that small your in uncharted waters.
• Hard to tell, but it looks like your upper sections of pipe need another support above the roof line.

The damper above the stove is only used to stop cold air from flowing back down into the house when the fire isnt in use. I control the fire with the inside slide dampener and the secondary burn lever. And of course cracking the door.

Honestly, after what everyone here has been saying, im debating rehauling the system and making the pipe run inside the house with A1 or the double wall piping I can buy from the original company... It will mean I will lose a corner of my loft space and have to rip a hole in my roof.... a spring/summer job to be sure so I guess no wood stove this winter.

 

[bholler]

The damper above the stove is only used to stop cold air from flowing back down into the house when the fire isnt in use. I control the fire with the inside slide dampener and the secondary burn lever. And of course cracking the door.

Honestly, after what everyone here has been saying, im debating rehauling the system and making the pipe run inside the house with A1 or the double wall piping I can buy from the original company... It will mean I will lose a corner of my loft space and have to rip a hole in my roof.... a spring/summer job to be sure so I guess no wood stove this winter.

I would not buy anything from that company. Even the double wall they are selling as flue pipe looks just like connector pipe to me I don't see any insulation at all there just an air space. Get your self a real chimney system that is tested and approved for your application. I have no idea about their stoves but they have no business selling chimneys.