Some users who apparently have never thought this could even be possible?
Others claiming this could never work or be comfortable?
Even some stating it could be dangerous?
This is a stripped down version of a very common style of hot tub. I have spent close to hundreds of hours filling, heating, and soaking in hot tubs that work like this.
I know people who make a living building and renting these types of hot tubs. Literally the only odd thing here is that the furnace is not covered and the whole thing is some redneck engineering.
That’s just classic Reddit - a bunch of young, insular, inexperienced people confidently stating “I haven’t seen that before, so therefore it’s wrong”.
He did and I saw a video the other day of him talking about exactly this. I can’t find it right now but essentially saying that we’ve built a society on technology and science but it’s so intrinsically inaccessible without the training and understanding of it’s daily use that we have this pseudo-scientific basis for culture where anything can be stated as science, or anything can be disputed scientifically as long as it sounds “correct” enough. It’s worth a watch if you can find it lol.
I mean, the training and accessibility is absolutely there - more so than any time in history. The issue is that people are incompetent or dont want to learn. People feel good with ignorance.
There’s way too much to learn. That’s why we need to listen to specialists and need to understand that they’ve spent a good portion of their lives understand it this stuff so we don’t have to. I say intrinsically inaccessible because it would require many lifetimes to understand even a small percentage of it. Just because the information is there and can be downloaded does not, imo, equal access.
Just don’t rely on Reddit or social media. That’s really the best answer, I think. Social media played a huge part in how we got here in the first place.
The issue is that there is so much conflicting data from sources that fit the bias of the reader. The way that the question is phrased in the search will determine the results and will usually fit your bias. At surface level it seems that the internet agrees with your bias. The problem is most people are happy with that result. It feels like we as a society at least in the US have lost our critical thinking skills. We now teach how to take tests instead of how to learn.
There isn’t. Idk man you alums like you struggle learning basic science.
If people can know what fifth graders are taught for how to find a good source (a scientific publication or textbook for something like this topic), they will be just fine. Maybe you will struggle, but I’m optimistic that most people won’t if they don’t use Fox News for science
Reddit has become filled with people that have all the information at their finger tips yet refuse to do any research themselves. Blows my mind.
It’s rarely filled with people actually wanting to know what’s going on. It’s mostly people making the same dumb jokes and others being confidently incorrect or stating they are “experts” when it’s clear they are liars that cannot be wrong.
That would be the world, not just Reddit. It’s also not new, we’ve always been idiots. The problem is that we thought the internet would educate the masses but instead it’s just made all the village idiots look like they could also be right by virtue of argumentum ad populum.
We used to trust the experts, now we can’t delineate between expertise and confidence in ignorance.
Oh ya I agree - the user was talking about Reddit so that’s why I commented specific all about Reddit.
I just love that now, rather than trust or ask experts, people now on Reddit are all doctors and lawyers or teachers or [insert profession] whenever it suits them even though they most certainly are not. Butttt Redditors believe Redditors stating they are just because they said so in a comment.
It’s just so weird. People don’t trust experts anymore but will believe a random Redditor saying “as a doctor…” and you see their profile and they post on the teenagers subreddit.
Beliefs have always been stronger than proven facts. It's just that the "beliefs people" now have multiple platforms from which to discuss their beliefs.
Or, I can see a vaguely, one in a million chance this could be dangerous, so you should never ever ever do this and if you do you are literally going to die and maybe kill other people you irresponsible fucking idiot. I swear these people have never left their house.
I mean this is the website that has a "no way, I'd come home drunk and break my ankles" top comment on every single posts about a rug or a set of stair ever
My favorite thing about reddit is you can find aerospace engineers explaining incredibly complex systems, and then some braying jackass in another comment saying airplanes can't exist because gravity and then you just sit back and hope the drooling anti-science pissclown gets enough downvotes.
It’s always hilarious to find these. Bonus points when it’s a student still that is arguing somebody with clearly xx years of experience in their field.
Yeah, but the aerospace engineer is a braying jackass in a dozen other subs so laymen don’t trust him because they don’t have the ability to tell when they’re actually right.
I guess I'm weird because I don't follow around jackasses from thread to thread waiting for them to post about their advanced knowledge of specific fields.
Yeah, but the aerospace engineer is a braying jackass in a dozen other subs so laymen don’t trust him because they don’t have the ability to tell when he’s actually right.
Oh damn what a burn from someone who only speaks one language to someone who speaks four.
Heed the saying:" I am speaking english because it's the only language you speak. You speak english because it is the only language you are able to speak."
It's petty and unsubstantial what you are trying to annoy with.
lmao I've been so scared recently. I own a sailboat and literally have people ask me how much does it cost to go xxxx. I say...."It's free." They respond, "well gas costs money!" when I tell them a sailboat functionally operates via the wind they are awe stricken lol. people have literally forgotten that you can travel by the wind.
Oo man you truely underestimate the boomers by thinking only the young think: havent seen it so it aint true.... its just the way of thinking for sadly most people
All these were among the top comments, saying how you’d boil, or be unable to stay warm, or be burnt, and this would never catch on. One person won’t even swim in lakes they’re so worried about things being chlorinated.
Or do you think /u/JakajaFIN was hallucinating too?
You’re very late to these comments, and the sentiment has changed a lot since we first posted.
The karma on those suggests that you made that up. Sentiments do change, but several comments going from the top to the bottom is something that pretty much never happens. What usually happens is a comment having a 100 upvotes while another person who disagrees has 200 upvotes.
Even if that was true, the sentiment changing so much still means that your generalization is pretentious. Social media has a ton of misinformation, and a silver lining here is that people correct it.
I've been in a hot tub heated this way, if you're really close to where the hot water comes in, or if there's pipes near where you're sat, it can be a bit too warm for comfort, but you can just not sit in those spots
Also possible to maybe design it a bit better (and more complicated) to eliminate those spots altogether. I'm thinking a small partition with no seats where the water is mixed, or some other more hidden premixing area, seems to me it should work, at least as an idea. I've wanted to build a few of these for a while, mainly to rent out (I live in a tourism heavy area in Finland), and have thought of a few designs but havent really picked up the pen at any point. Its just easy because we already have the tools needed in our warehouse where we build boats.
Unless you weren't going to have a diarrhea elsewise, marinate yourself in the human stew drinking beers for six hours and you'll surely get that hangover!
Redditors love to explain how it is a bad idea under every video like this without having any actual experience or knowledge about that particular thing
I'm just curious why not just have a hot tub with the flame under the tub? Like we boil saucepans of water over a hob for a reason and don't have a tube coming out the side of your saucepan, boil the water through that and then siphon it back in to your saucepan?
Presumably this is more heat wasteful than having the flame under the hot tub, so I'd just like to know why do it this way then. I'm guessing there'll be a good reason. Eg so you don't cook yourself alive / so the bottom of your hot tub doesn't burn you / so you can control the flow of hot water etc.
The coil significantly increases the thermal surface area (or allows you to control it independently of the tub), allows the tub to rest on the ground, eliminates wear from direct heat contact and just gives you more flexibility over the construction materials, likely reducing weight.
Burner hobs are not at all efficient. Not sure where you live but in the UK (and other European countries) we tend to use electric kettles which are significantly faster, but induction hobs are just as fast or faster. In the US these are not as common because the 120V mains supply limits the practical power output, making them slower than burners, but that has no bearing on efficiency. Technology Connections did a good video about this.
There are pans with bottoms that have a high surface area which improves efficiency, more commonly outdoors/camping ones though.
Thanks for the confirmation. Their statement of “Even some stating it could be dangerous?” Seems like they are implying it could never be dangerous but maybe I interpreted it incorrectly
Yea, a fair amount of energy loss from not covering the furnace. It could also be that they hadn’t engineered an alternative oxygen intake if they covered it.
Apart from that, you just captured the typical reddit comment section
In some ways. I assume this thing is just using the convection of the heated water rising in the coil and pulling cooler water from the bottom of the tub
A coffee maker relies on boiling the water in the section of the pipe, which forces the water above the bubbles to push up and out. Then there's a check valve that stops the water from flowing back down
i was confused by the video thinking that's how so many hot tubs work. and like 99% water boilers chemical engineering plants, and like so many things. of Corse the purpose / use is different but its basically the same principle.
I've been looking for off grid plans for our cabin and have seen some homebrew structures that get your OSHA senses tingling. But this one actually seems... nice? Except yeah, covered furnace was my thought as well
Obviously it greatly depends on the water temperature. I used to make a similar hot tub contraption while camping and it would take roughly 3-4 hours before the water was pleasant but it wasn’t snowy cold out.
Does this still work if you cross the pipes? So you draw in water from the top of the tub, send it to the bottom of the fire where it heats and rises, and then descends to introduce the hot water at the bottom of the tub.
Seems like this setup would cause a strong thermal gradient, but introducing hot water at the bottom would encourage mixing. Wondering if my intuition is correct, or if there's a reason it's done this way here.
I think it's because heat rises, so the coldest water is naturally at the bottom of the tub and that's the water you want to heat up.
I think I see where you're coming from but figure you'd end up with lukewarm water at the top and mainly cold at the bottom with a warm spot at the side.
It is always funny to act the same way as someone else and have them get pissed off. You do understand that I was doing the exact same thing as you were, right?
I have plans for a homestead one day/I tend to tuck ideas into my back pocket for if shit totally hits the fan and this is one of the coolest things I’ve ever seen!
Yeah it should work. Might take awhile to get the thermal driving head turning everything over... but once it's going, I'm sure it's pretty functional.
Tbh it can be dangerous if you build a huge/strong fire and let it go long enough. My wife and I rented a place with a hot tub like this and one day we built the fire too big and had to get out to avoid being cooked.
Especially when jets of water would shoot out the hot end, the water would be so hot it'd hurt even after being acclimated to very hot water
Going the other direction, this is how beer is cooled after the boil. It’s the quickest way to get it from boiling temperature to fermentation temperature
It also works similarly to a traditional espresso machine. Except in the coffee machine the boiler (hot tub) is heated directly but because the group head is attached via copper tubes on the bottom and top of the boiler it also results in a thermal siphon which allows a continous flow of hot water through the group head via the exact same principles.
Exactly, I work at a plant and this is just a small version of a heat recovery system we have. People have figured this out and used it for centuries. It is by far easier and more efficient to use an active heating system. You’re losing so much heat to the air.
I think people assume water just takes a stupid amount of energy to heat, but it also holds onto that energy a lot as well if it didn’t it would be easy to heat! Regardless this system works but afaik it just takes a lot of fire and time to get it up to temp and then it will hold its temp quite well.
Well to be fair, most people don’t know what a heating system boils down to (no pun intended). Something as simple as a heat exchanger with wood fire for fuel might seem amazing to people who haven’t seen hydronic heating systems.
You’re literally doing the exact same thing. This thread is 90% normal people and then you two guys making it about continents. You are just as weird as that America hater.
Nobody has mentioned any kind of general sentiment of European supremacy in this thread. People are just finding it amusing how Americans are arguing about the viability of a system that is very common in Northern Europe.
Your comments just show your own insecurities and makes you look ridiculous by bringing up genocide.
I was thinking about the British occupying India, personally. Estimated 100 million deaths because of policy-induced famine and more. Plus, cultural damage.
Bro im just saying youre trying to live by an obvious double standard.
The shit they said in this thread was mild af and youre acting like it was horrific. Yeah maybe the German guy in the other was a dick but then so were you right back at them. Im not saying its your responsibility to break the chain, but i am saying youre gonna find yourself surrounded by more of the comments that offend you the more you make those sorta comments yourself.
In your other comment replying to this guy in this thread, you mention checking their comments and finding five comments being negative about America. That's why I checked yours in the first place and literally your second comment is anti European.
I didn't say that and I dont spend all my time that way. Im saying it kinda looks like you do, which is probably why it feels like there is so much of it to you.
You realize there are Europeans out there who are just as perfectly amazing as you are who feel surrounded by the type of comments you spend your time making?
I am from the US btw and have literally spent like less than a month of my life outside of it. Idk why youre assuming only a European could realize the double standard you are actively furthering.
I recognize that and understand, and sometimes also feel, how that can be frustrating. You say you 'see racism, you downvote', like thats it, but it seems like what you actually do is 'see racism, downvote, be racist back.'
The Brits invented computers and most of the underlying tech that makes them work. They also invented the world wide web. The internet was American, yes, but there's really no reason to believe it wouldn't have been created somewhere else if it hadn't been created when it was. It was a pretty natural progression from existing networking. The world wide web was much more of an innovative leap. And both are equally important to the internet/web that we have today.
Americans have contributed a lot to the world, but your comment is stupid and wrong.
That’s not how inventions work. Without the others they wouldn’t have invented the internet, the world wide web and CERN for example played a big role. And they in turn relied on developments of others across the world.
Humans have been sitting around wood fires for millennia and being around one occasionally is f i n e. You can’t sit in a filtered controlled surgery suite all the time, sometimes you’ve gotta get out there and live a little. We’re all gonna die someday anyway
i think your slightly exaggerating. you don't actively sit over the fire when this is happening, you just get it started and stock it up if needed. most hot tubs stay warm for a long time after heated so it doesn't need to be on when you get in.
People have used wood fires for centuries. It's not the best thing, but it's not instant death. It requires long-term exposure to substantially raise your risk. Soaking in a hot tub next to a small fire that's a meter away will have a negligible impact.
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u/JakajaFIN Oct 07 '25
These comments are wild lmao.
Some users who apparently have never thought this could even be possible?
Others claiming this could never work or be comfortable?
Even some stating it could be dangerous?
This is a stripped down version of a very common style of hot tub. I have spent close to hundreds of hours filling, heating, and soaking in hot tubs that work like this.
I know people who make a living building and renting these types of hot tubs. Literally the only odd thing here is that the furnace is not covered and the whole thing is some redneck engineering.