Can you convert a single hose AC to dual hose ?

Can you convert a single-hose portable AC unit to a double-hose setup and gain tons of efficiency ?
Read on.
The answer in short is yes. But it's way more complicated than just fixing a second hose to the back air inlet.
In a dual hose AC unit there's a separation between the high and low pressure chambers to make sure that the two air sources don't mix. This is missing in a cheap single-hose unit.
For my unit, I had to seal up the area surrounding the compressor and condenser so the air would not get pulled in from the cold side of the device.
Just attaching a hose even lowered the performance.
The final result is surprisingly effective, and beat my expectations.
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[@morganc5561]

Just finished this upgrade on my old Whynter ARC-10B, and the difference is astounding. It is 120% worth it to pull the covers off the unit and tape over the open space, now this little AC actually performs worth a heck and gets my living room cold! I had been taping cardboard boxes with dryer hose over the intake for years, resulting in a poor man's "dual-hose" setup, but now the hot and cold sides are fully isolated and the performance is just wild. I used 6" insulated ducts (for hydroponics) for intake and exhaust, there is *very* minimal heat leakage from the exhaust hose, and the AC even runs a bit quieter too. I paid ~$250 for this AC in 2014 and it now runs better than ever! Thank you for this video.

[@dherrendoerfer]

I have a second video where I add a third pipe to the intake of the evaporator that pulls the air from a higher point in the room - that adds another 15% of efficiency easily.

[@pinkipromise]

to save you 30min, modifying the host is not enough. need to insulate the inside too

[@mikkihintikka7273]

us that so?

[@chadialaouisoulimani8188]

I'm glad I watched the whole video since he explains how to insulate, and for 60% efficiency, it's worth it.

[@bababababa]

31:45 for the result. I watched the whole thing and fell asleep and woke up when my phone fell to the floor. awesome looooong form content.

[@Psythik]

Yeah it annoys me too when KZbinrs make stupid-long videos like this one to answer a simple question, because I'm just going to fall asleep, won't learn a thing, and the uploader won't get any ad revenue from me cause your phone knows when you're asleep. It's best to keep it short, simple, and to the point. KZbin *really* needs to bring back the 10 minute time limit for video length.

[@ivanmihoci2936]

Thank you so much for the video. I followed your steps and did the almost exact modification to my device. Even if disassembly was a real frustration, the final result was worthwhile. I haven't measured the temperature differences, but i can say for sure that the vacuum effect is no more.

[@peterheinz8776]

I did this on my Hisense 12000btu and it turned out great, turning on and off like an air conditioner should, and saving energy.

[@anonharingenamn]

Great video. I just got an old AC from a friend, and I can see the internals almost look identical to mine. Thanks, now I know I'm screwed and won't be able to do this haha.

[@Stacy_Smith]

For those of you that doesn't have access to a 3D printer, CHECK OUT THIS VIDEO: kzbin.info/www/bejne/opvYqoyNi7B1iJI

[@frenchcreekvalley]

Interesting video. A very good and thoughtful presentation on your part!!! I just bought one of these a week or so ago, without doing enough research. Of course I learned about all the issues with the unit first hand. Lots of people do complain about the loss of efficiency these things present, but they usually miss the very important point that they also suck in outside humidity, especially if they are left running all night, when outside humidity usually gets very high. I took mine back and got a full refund just yesterday. I am making a video myself to try to caution people about both the cooling efficiency AND the HIGH humidity problems of these "One Hose" portable air conditioners.

[@dherrendoerfer]

Great point !

[@sic19]

great video, good information...just had to watch it at 1.5 speed to not fall asleep xD

[@Gizawar]

For me modding my protable ac worked great. I have 9000btu AC that had only exhaust pipe and my room would cool down from 22°C to around 18-19°C. After I added intake pipe it goes down to 16-17°C. I used solar powered bathroom fan which is now blowing air into intake pipe. To mount my 125mm pipe to AC i used zip ties and tape all around it. My intake and exhaust are ~5m apart on two different sides of the house.

[@dherrendoerfer]

Very nice!

[@tomilipin]

Did you open the unit and did some modifications? Or is it enough to just stick an additional intake pipe going from the ouside to the intake vent of the unit?

[@Gizawar]

No, i just added intake pipe and taped around it including some seams. Difference when my solar intake fan is on is 10°C at the cold air blower vs 12-13°C when the solar fan is off. I guess that 2-3° difference is enough to make my bedroom noticeably cooler. Also my intake is on a shaded part of the house while exhaust is around the corner, just so the intake wont suck hot air back in.

[@tomilipin]

@@Gizawar Awesome news for me, thanks for your reply :) Will do the same. At first I was really discouraged by all the hassle with opening the unit and doing mods. Will try the intake pipe. Thank you again!

[@mjay776]

@@tomilipin did it work for you? I was thinking of trying it. And where do you get the extra hose at use a dryer hose or something?

[@jammi__]

The price difference simply comes from the additional hose and slightly larger package. I made a conversion like this years ago back when I still lived in an apartment building, and the conversion worked fine, and the 2-hose model would've been identical apart from the hose and hose connector. Your duct tape and zip ties solution is more elegant than mine was though, I did 3D-modeling and 3D-printing to adapt a second hose to mine with a piece that looks like the factory 2-hose model. The situation in Finland is that neither buyers or sellers are aware of the benefits of the 2-hose models, so they're nowhere to be found. Therefore we only have single-hose portable units in our market.

[@Bomtoi]

Would there be a chance that I could check out your 3D models? I happen to have a 3D printer as well and was thinking about doing the same. Jos sattus olemaan vielä Ströme 12C verkkokauppacomista niin selviäis mallintamattakin 😁

[@Paulydude2000]

done this very same thing to a larger fedders unit....works well, much better than only one inlet hose

[@acmelab68]

I saw the video of "technology connection" months ago. And although he has a tendency to describe everything in exaggerated detail, I didn't really understand it. Now that I've seen your video, I understand what he was trying to explain. Honestly, sometimes the guy confuses me more than he enlightens me. Well, anyway. I, too, have been thinking about buying an AC for a long time now, but I didn't know which model (technology) was right for me. Thanks to your video I am one step further, but the problem with the German windows still remains. In any case, thank you very much for this very informative 'different' video :)

[@jeremiahhively3025]

I love the video, I like how you take the time to explain everything

[@0-Will-0]

Dirk, as someone who knows a lot more about AC than me, I would value your (or others) opinion on an idea. Essentially, moving a portable air con unit from venting out of a window to venting into a room, which is sacrificed as a hot room. The unit would sit in the internal door frame, which would then be sealed. The window inside the room would be open. The unit would have the outlet duct pointed in the direction of the window and also have input air come from the window / outlet hose. There would be about 6ft between the end of the duct and the window. The sacrificial room would get hot but a lot of the heat would eventually make it out of the window. The motivation behind this idea is to have some effect of a dual unit in cooling the rest of the house, as the cool AC air would be on the living side of the door frame and all input and output air of the AC would be on the other side of the door frame. . I also have very awkward windows for ducting out of. I hope that makes sense and sorry for the rambley long post.

[@dherrendoerfer]

I suppose that would work - yes! But keep in mind that you'd be creating one heck of a hot zone in that second room. And that would be seeping back into the rest of the house while the unit's off. But you'd be cooling that one room effectively. The AC unit may however suffer from a loss of efficiency due to the hot intake air on the condenser. For what it's worth you could just pipe the cool air through pipes into that cool room, making a dual hose setup that way as many commenters have already suggested - putting the AC on the Balcony and having a dual hose setup to the inside.

[@cgcornel]

@@dherrendoerfer, this was my idea also! Excellent! Thank you very much for your video! It saved my time and money!

[@stauffap]

There are a lot of things you could have done. You could have used a hose with a larger diameter and you could have made the hose shorter. You could have also designed the attachement of the hose to the unit differently. After all most air will always take the path of least resistence. So the reason why a lot of the air didn't want to go through your hose was that it offered too much resistance. So the unit prefered to take air from other sources, which is probably why you had your problems. The less resistance in your hose the more air will come through the hose and the less air will take the other, undesirable paths.

[@stauffap]

Another idea is to not even connect the second hose to the device and simply let the warm air blow at the bottom of the device. That way the device can "chose" to take air from the room or from the second hose. It will take some air from the hose so this alone should improve the performance of the device. Of course the same thing as before applies, but to a lesser extent. A wider and shorter hose will feed more air through the hose and into the device, instead of feeding the device with air from other cracks in the room. I think that this is one way those devices operate. The devices sucks in air from other (probably colder) rooms in the house and heats the entire house up, while cooling the one room with the device. Probably not a good idea. Maybe the is how the device is able to somewhat hide it's glaring inefficiency.

[@michaelcurce2056]

This guy didn’t use a large enough tube. I used 6” hvac duct and it worked great!👍

[@jasonbrown467]

i have two of these type of units that have a heat mode, sitting here in shorts in my house and its 29f outside at the moment. the unit i use by default has two hoses from the facotry, for the days it has got down to about 15f i fired up the second unit, but since it only has one hose i vent the cord air down into my basement and it seems to be working, but i know its making a cold draft some where i have been experimenting with this stuff, and found air flow is key, so i bought a variable speed duct fan so i can sit down and find the sweet spot. might set up some temp sensors and relays to automate it once i found the sweet spots. i think the duct fan is only about $30

[@ATomRileyA]

My portable air conditioner had its exhaust fan blow up with a big bang and the fan blades were broken, could not replace so i deactivated the that fan and as i did not want to just throw it away i got a 5 inch extractor fan and fixed that to the back of the unit so now i still can use it but i noticed right away this 5inch centrifugal fan seemed to do a far better job cooling than the one internally so that is now how i use it and has been working like that for years. I had to use a eco plug thing for automatically turning your monitors and such off for computers so that the external fan turns on when it senses the the AC is on but also turns itself off when AC is off. But it made me think if i was to get another one of those fans for the intake side so it was in a push pull arrangement would it improve the performance further still as you would be increasing the pressure through the unit. Might be something to try on your intake side so that your using more compressed air on the intake which would then get fed into the extractor fan and might improve performance. Great video btw.

[@autismlifehacks5233]

Converting single hose units to dual hose sounds like a great life hack because it's easier to find features such as heat pump, inverter, and self-evaporation. I was thinking of maybe buying a single hose LG DUAL inverter AC and converting to single hose but after watching your video, it looks like it's better to play it safe by getting a dual hose version. The upgrade would be a fun idea when it comes to existing units. It's easier to find portable AC's where AC installation is banned.

[@unclebillscamping]

Even dual hose units pull some room air in. They are not totally closed systems. The main problem is intake size by reducing the size the intake the unit struggles to find enough air to cool and push out.

[@dherrendoerfer]

Agree, but this unit is completely open on the inside. Adding a barrier between the hot and cold side was a good improvement.

[@TechCharted]

I just convert my portable ac from single hose to dual and i can feel That it is still pulling some outside air in room and creating some air pressure. Is that normal to have that much of air pressure?

[@brudevold62]

Close on the Heat pump description what you described was A/C cycle pretty through and accurate and what happens in both coils and refrigerant... But a heat pump has the ability to reverse the roles and responsibilities of the coils so it can cool or heat the conditioned area.

[@dherrendoerfer]

I think you are referring to a reversing valve, the A/C is a one way only heat pump. Put a reversing valve in there, and you can go both up and down direction.

[@brudevold62]

@@dherrendoerfer Correct from what I understand the reversing valve is what separates Heat pumps from straight cooling units. Did some more research and the term heat pump does not have a singular definition and is not isolated to one industry. Great job on the video. The A/C and Refrigeration cycle is all about the heat transfer

[@mik13ST]

@@dherrendoerfer Do you actually need a reversing valve for using for heating? It should be enough to just use the intake and exhaust hoses for the evaporator instead of the condenser, right? One would have to seal off the top area instead of the bottom one which seems to be more challenging (since neither inlet or the outlet are hosed from the factory) with this model, maybe.

[@dherrendoerfer]

You're right, you don't. You could place the device outside and have it blow warm air inside. Not sure how well this works, because the cooler may refuse to work with such low air temperatures.

[@mik13ST]

@@dherrendoerfer I plan to heat (e.g. with a resistor) or bypass the thermostat so it thinks it's way too hot so it runs. Then I need my own thermostat and switch power to the whole unit. This should work in theory. Anyways, thanks for the video.

[@kennym2035]

Arizona it gets 117°. I don’t think 2 hose is sufficient. I don’t think the condenser coils will get cool enough so it’s better for me to just have a single hose and deal with a little bit of the negative pressure.

[@dherrendoerfer]

117 deg F should not pose a problem for the condenser. You might want to insulate the hoses then though.

[@penangtv6108]

There's a problem with your printed baffle in that it's like a "round peg into a square hole". Which is a problem because you're basically "reducing" the size of the original hole, and the duct tape to the right is plugging up more. You want to attach a box or a Tupperware which is bigger than the original hole, then attach the hose baffle to this box, which will create a standoff so that the edges of the baffle doesn't block air and eliminates the blocking duct tape.

[@dherrendoerfer]

True.

[@bahorized]

The size is already limited by the hose anyway, even if you increase the last 15cm. Unless you put a bigger hose it won’t matter.

[@dherrendoerfer]

@@bahorized It's not that much of an issue - the restrictions do not suffocate the turbo fan on the exhaust - the fan rpm did not change before/after the mod, and the air flow is still strong enough.

[@richardc1983]

​@@dherrendoerfercorrect but you want to give air the path of least resistance. A smaller hole will allow the unit to take air from other areas where there is no resistance. Fitting a larger return cowl would have worked much better.

[@scottk3292]

I'm in process of building a plenum around the intakes for both coils, so that all that air will be drawn from outside. My idea is to force more cool air into my home so it will go down the hallway and reach the bedrooms. Due to the volume of air it needs to draw, I'm using 8-inch tubing. Some systems may suck, buy mine blows.

[@dherrendoerfer]

It's 16C here in Germany right now.... I might as well put the thing outside and push the warm air in.

[@scottk3292]

@@dherrendoerfer As a temp solution, I have one of my units outside, pushing cool air in. Considering what you demonstrated on the lack of isolation, that might be the best approach for now.

[@sseforsale922]

Ok. The only reason you would need insulation between the condenser/compressor and the evaporator is because you are restricting the intake side of the condenser/compressor. Which is what you did with the printed part. The cold air blowing over the evaporator should go into the room but isn’t because you’re creating a vacuum by the hot exhaust system. You are also decreasing the efficiency by only allowing air to cool down part of the compressor/condenser system by restricting air flow. Optimal setup would be to box in the the condenser/compressor intake so it only draws in outside air and can do so through 100% of the holes that are designed to be in the machine.

[@dherrendoerfer]

No, the insulation only prevents the fan from the condenser to pull air from anywhere but the hose feeding in the outside air. Without, the fan can pull air from anywhere because the case is more or less just a skirt. It then creates a slight vacuum in the room and pulls air from the lowest point in the room, where it's at its coldest. The mod simply improves the separation of volumes.

[@Lvvcassss]

It's better to do another thing. I added two hoses to the cold circuit, made a window flange with two holes and put the whole unit outside. This way noisy unit is outside and ondensate drips outside.

[@sfesfawfgasfhga]

Note that some newer units use the water to cool the hot side, which improves efficiency a bit & can significantly reduce the need to drain.

[@melvinphuti515]

How is it working for you? Been wanting to do something similar but for heating, using a cooling only portable ac reversed, with the exhaust pipe pumping in hot air and circulating it through a second pipe that goes to the compartment that sucks in the air that was supposed to be pumped outside. It worked when it wasn't too cold, but at night when it was cooler the performance dropped. In the afternoon when it was not too cold I noticed that the performance of heating was improved drastically compared to the heating performance of my other single hose portable ac that is designed for both heating and cooling. I'll continue with the experiment, this time with sealing the other compartment as done in this video

[@Lvvcassss]

@@melvinphuti515 It's the second season and no issues. I sealed the unit wherever possible with silicone, sprayed all te electronics with pcb lacquer, relocated indoor air temperature a bit so it measures temp of air sucked from my room, not the ambient and also extended the IR diode to the window so I can use remote ;) I live in an apartment so I have central heating from city and it's cheap.

[@melvinphuti515]

@@Lvvcassss thanks, that's interesting. We're blessed with good weather here in South Africa, just not blessed with cheap heating, which is only needed for about 2 months in a year, hence the interest in a cheaper way of heating space. Thanks for sharing, I'll apply what you did for my own purposes. I'm sure it will work, especially given the the ac will be under a closed patio

[@wayditay9288]

This could be an interesting and simpler solution to my needs as our older portable single-hose unit is quite leaky, so separating the chambers by sealing them will be next to impossible. So please explain in more detail of your 2-hose connection -- is it a modification of Dirk's plan? Also, did you connect the unit with an extension cord, and if so what size or gauge did you use?

[@michahalczuk9071]

Nice video. However, I've seen other videos showing that some AC units ARE insulated while being single hose. It's just device dependent, but for to remember!

[@dherrendoerfer]

yeah, research first buy then.

[@iair-conditiontheoutsideai3076]

I solved this by putting copper insulation tubes around the entire bottom forcing to suck in more air from the diy intake hose

[@kdmq]

I did this but it looks like my unit actually discriminates very nicely between evaporator and condensor airflow and there is not too much pirate air coming in from the bottom of my unit. I am freezing my ass off standing in front of it. :)

[@dherrendoerfer]

What unit do you have ? I've been trying by best to source some better units, but have come up blank - Most sellers won't even give you anything when you tell them your're gonna tear it to bits and measure its efficiency -;)

[@peppermeat8059]

@@dherrendoerfer yeah, most units that are dual hose are already sold, i am looking for a portable a/c because window ac would be energy consuming and not work as intended aswell as the split type because its expensive for installation, i dont want the outdoor unit to be outside my wall, i do not really like permanent installations, im deciding hard, portable ac or split type?

[@adrian4mani]

@@dherrendoerfer this is 1 year old. I have a trotec model 3500sh and it came pretty nicely sealed. it has an effieicy rating of A, maybe that helps

[@realcartoongirl]

same, mine was not completely sealed but a second hose was enough

[@rafaelmorales4070]

Tried it without insulating the inside. I’m getting better performance out of my portable AC.

[@glenraymond379]

You need to edit more man.. You said in the beginning of the video that you will tell us if a dual hose is better then a single one. I'm at 6 minutes in your videos and I still don't have an answer. I'm taking the time to tell you because i'm like you, I like creating stuff and trying new things, i'm sure that you would get a lot more view if the video was 10 minutes instead of 30 minutes.

[@DXmYb]

Length of this video is 1/3 of a movie

[@gir1258]

Did you miss that the length of the video is 31 minutes? Did you also forget that you can skip around the video…?

[@tazyboy28]

Came here to say this. Taking to long to get to the answer. I understand your speech is slower but 30 min videos turn people off and they end up giving up.

[@moosenbeans903]

You are bitching about free info. Bet you pitch a fit when Mc Donald's is out of free catsup. Karen it's free. Go to the library next time.

[@somethingsomething404]

I’m watching at 2x and made it to 10 mins

[@Bones469]

I am getting ready to do this so I looked to see if anyone else has done it... and Viola 🎻 I found your video... If I really get creative I'll blow that hot air through a small radiator to heat a small pool or jacuzzi. What was to sue a small blower to help bring up the positive pressure from the outside air but even then might be a fail if you it began blowing into the other compartments of the unit.

[@dherrendoerfer]

I'm currently getting another video ready, using a different AC that is far better suited for the conversion. I'm trying some of the mods suggested in the comments of this video.

[@richardc1983]

Would have worked better if you had used a funnel type inlet to allow air to spread evenly over the condenser coil... You've got air being directed at one point on the coil so now it's not removing all its heat from the circuit.

[@dherrendoerfer]

I currently have a super cheap 7000BTU unit that's perfect for dual hose conversion, because it already comes with pretty much perfect chamber separation. I'll try the funnel mod on that one.

[@davidreynolds4684]

I haven't seen the unit yet but all of these I've dealt with have two exhaust ports. One usually has a cap. The two are for convenience of where your window is located left or right of the unit. Now looking at your unit where you put an adapter that shouldn't be an exhaust port. Warm air should only exit from the designed exhaust port. The one you connected to is an intake you don't want that going out doors as you'll be sucking in hot air. I may have misunderstood your explanation at the beginning. Now you're talking about two hoses. Those are both exhaust ports. At least in the dozen or more I've used. An easy explanation is place your hand in front of every vent on your unit. If you feel warm air exiting the vent then it should be ported to exit the area you're trying to to cool. If you feel no warm air at any vent then it's an intake. If you feel cold air coming out of a vent it's obviously a cold air vent

[@dherrendoerfer]

Yes and no - I add a port for the second hose where the air that will be exhausted outside is drawn in - this hose is also now pulling air from the outside. The fact that this air is hotter now makes no difference to the phase change heatpump, because only the temperature difference across the condenser counts. The second point is to make sure that the two hoses don't introduce hot or humid air into the room you are trying to cool. So the hoses and the AC itself must be well insulated/airtight. Lastly we don't want the unit to create a vacuum inside the room, because it will then pull air from anywhere - the airtighter the house or room the more the efficiency drops.

[@buddysteve5543]

Thanks for your info! I was just thinking about doing the same thing on my Delonghi portable air conditioner! I'm debating rather to modify it as you did or simply sell it and use the money to buy a dual portable air conditioner.

[@richardc1983]

It worked for me, I just used a thick black bin line with a corner cut out to create a larger return air point.

[@flamy111]

Hey Dirk, very informative video! Incidentally I have recently 'fixed' my unit like that by 3d-printing a replacement for an exhaust connector. I had a thought watching it, instead of insulating the whole thing, what if you force air through the intake? For bonus points if you add a fan at on a side of a window instead of side of air conditioner to reduce noise. My assumption is that you will need to insulate things a bit, but maybe without taking the whole thing apart.

[@dherrendoerfer]

I'm not sure about that ... the risk is that you end up pushing hot outside air inside, and this would have to be one hell of a fan ....

[@Asgardt13]

Very useful thank you very much friend!

[@sean8476]

it looks like you are cutting the intake by more than 50%. you need a bigger intake or an inline fan to increase the air flow

[@dherrendoerfer]

Yes, that would probably make it perform even better.

[@squidben5780]

I would suggest to 3d print a rectangular adapter to enclose back and side and shrink to a round tube ending in the hose for inlet of exterior air. maybe less restriction ?

[@dherrendoerfer]

Removing any restriction is a good idea, but keep it tight, you don't want the extra hose to leak hot or humid air into the room when the unit is not running.

[@RedSunFX]

How did you come up with a 60% efficiency increase? Before insulating, you cooled down by 2°C per 30 minutes. After insulating, you cooled down by 5°C per 30 minutes. Meaning, the unit becomes 2.5 times as efficient at the end, that's an increase of 150%. (5°C/2°C=2.5) (2°C + 2°C * 150% = 2°C + 3°C = 5°C)

[@dherrendoerfer]

Yes ! A performance of 150% is an increase of 50% over the previous value. It's just the wording that implies that 'increase' means above 100%

[@veeman501]

Great Work! Keep it up!

[@npvolainvkadv]

This unit was designed to operate in a vacuum. In a vacuum all pressures are equal so air flow through the evaporator is not being salvaged by the exhaust blower. Take away the vacuum then the only vacuum that is present is that of the exhaust blower which results in indiscriminate salvaging of any air to satisfy the requirements of the blower including but not limited to the evaporator coil. Added to this is the restriction of inlet air through a hose. All is not lost however. All you need to do is install a cheap blower to the inlet side of the air supply. This will overcome the air restriction caused by the hose but also apply an equalizing pressure to the air flow of the unit stopping the salvaging effect of the exhaust blower.

[@dherrendoerfer]

in general, adding a fan to the intake will transport heat and humidity by/into the unit, possibly contaminating the space you want to just cool - the fans in the AC are powerful enough to draw enough air even through several restrictions.

[@npvolainvkadv]

@@dherrendoerfer so you tried it then or are you guessing?

[@dherrendoerfer]

@@npvolainvkadv I have experimented with the effects of a constrained airflow regarding the efficiency and airflow of the turbofans in these units. The results were not in favor or against having a slightly constrained intake or a long hose.

[@npvolainvkadv]

@@dherrendoerfer Reducing restriction and adding neutralizing pressure actually would assist the units blower/fan moving air through the evaporator coil increasing the efficiency of heat absorption and evacuation of heated air to the outdoors. As far as the contaminates argument goes ...that does even make sense since you are drawing air from outside in any case. Another point...it seems as though there is no filter screen protecting the evaporator. Simply add one in the process. Iam in the process of installing a window ac unit into a chambered cabinet and twin hosing that unit. Strata bylaws prohibit window ac's here. I believe this is the way to go since window ac's coils are sealed from each other for obvious reasons. Just have to separate evaporator inlet and exhaust air flows with the use of partitions and chambers.

[@dherrendoerfer]

That sounds like a good project - I've seen window units recessed into walls from the outside before - some years ago they were very popular in small hotels on the ground floor.

[@rob4197]

@15:15 - if both hoses were facing the sun, the air around the hoses can get hotter. A single hose with a basement window crack open will give good results. In an apartment/condo, most of the incoming air due to negative pressure comes from the cooler hallway.

[@pollos6807]

Hi great vid!! Can you show how you opened an put the machine together. I'm afraid I will fail doing this myself otherwise. Other than that have a good day! 🇺🇲🇺🇲 // Also it would be nice to see how you put on the tejp.

[@dherrendoerfer]

I currently have no plans to take it apart again, I've already stripped out two of the case screws, and right now it just needs to work. Maybe when fall comes, I may take it back to pieces.

[@joearokis8265]

Just a thought, what if instead of blocking so much of the original intake you encapsulate the whole intake and use a much larger intake tube? I think you're forcing it to take additional air from everywhere else because the intake is too restricted. Just guesstimating, but it looks like your original intake was at least twice the size of the exhaust. I did mine like this using cardboard boxes because it was what I had at the time. Worked much better than before.

[@dherrendoerfer]

Yeah. I isolated the intake chamber from the rest of the machine, the turbo fan can handle the pressure drop just fine. Performance has very much improved, and the device does not leak that much ambient air into the room.

[@richardc1983]

To get better temp control relocate the return air sensor so it's point outside the unit.

[@RichardLewisCaldwell]

Where does the room air now enter? Leaks?

[@dherrendoerfer]

The evaporator still has inlet and outlet vents, there's no change there.

[@peterdanielantal352]

Hi! Can you tell me, what is the differance in efficient, or celsius, if I would do the same thing, and make it dual hose?

[@dherrendoerfer]

My performance gain was about 40%. The temperature is the one you set on the unit, but it gets there faster, and the on/off cycles are less frequent.

[@peterdanielantal352]

@@dherrendoerfer oh, that's really great, thank you, I'll try to do it, with my unit

[@PaganWizard]

Where can I find the adapter that you 3D printed???

[@Hi-levels]

Midea duo inverter has a crazy SACC value 14000 btu and i believe 12000 sacc.. has dual hose system. And inverter too. I have a chill flex pro , curently blasting hot air from chimney ,used some foam to make myself an insulated base. Lol. The hose gets frigging hot i ordered an insulator to the hose even that will make differnence. If i move the unit to my room i can use window locks and do 3D printed mod for dual hose but im not opening the up lol

[@dherrendoerfer]

The Midea duo is not available anywhere here. I made a video about the lite units (7000btu), and it comes with all the isolation already in place - it's super cheap and usable too.

[@Hi-levels]

@@dherrendoerfer it is sad. Midea duo is amazing i hope they make it to europe. I ended up with Electrolux(aeg, frigdaire all same) chillflex pro 12K BTU model. It is single hose and you literally need to open room door ajar and you can feel air comes into the room. If you dont do it in a sealed room, it doesnt cool it... so stupid. I already ordered the 3d print for the vent place and will go double hose. Also i ordered an insulator for the main exhaust hose. Stuff gets crazy hot... i sont open up my unit lime you did because it has warantty but maybe it the feature

[@socks2441]

great video, what was the long term result, did anything ever overheat or get damaged etc? i am thinking of doing this myself. i would buy a dual hose but they are literally over 4x the price. so i will cjust buy a cheap single hose unit and then do this. i will also keep the hoses as short as possible and probably raise the unit so its basically in the window. hopefully that will make it as efficient as possible.

[@dherrendoerfer]

It's still going strong, if anything I've created a cold bridge to the aluminium wrap, there's a drop of condensation under the machine sometimes, but that's it.

[@NebulaLuna]

Alright I just spent a few hours doing this. Taped up the same area on mine, didn't have any thermal foam so I didn't do that part. The intake hose in the window is sucking a good amount of air in from outside, I felt the air under my door and the breeze coming from the rest of the house seems a good amount less than before any modifications. I assume this area is from the dehumidifier + some extra stuff making its way into the modded intake?

[@dherrendoerfer]

I think so. Getting the condenser loop 100% isolated is probably impossible. That's why the few dual hose units are so expensive I think.

[@TechCharted]

I just convert my portable ac from single hose to dual and i can feel That it is still pulling some outside air in room and creating some air pressure. Is that normal to have that much of air pressure?

[@briand8090]

The explanation for how the A/C unit works os not accurate. The air inside is used to evaporate the refrigerant, which removes heat energy from the air. The air outside is used to remove the heat the condensing the refrigerant from a gas to liquid.

[@dherrendoerfer]

I don't know which mention of the process you're referring to, it comes up a lot in the video. Yes and no, the phase-change from gas to liquid is actually done by the compressor by raising the pressure to a point where the preferred state of the coolant (at ambient temps) is liquid. The coolant leaving the compressor is in agitated state (very hot) and it's cooled in the condenser by (from) outside air. When the heat energy added by the has been bled off by the condenser it's calmed liquid. The valve or capillary tube then lowers the pressure. The coolant is still in liquid state at this point, but suddenly very cold, it now (requires) absorbs energy to go to its preferred gaseous state at low pressure.That change preferably happens in the evaporator, where inside air is passed through. It's the different pressure states that allow for the higher efficiencies that heat pumps can achieve, not the evaporation and condensation change, if it were, then the efficiency would be

[@briand8090]

@@dherrendoerfer The actual transfer of heat is from difference in thermal mass of the two systems. The fluid is the transport mechanism and the valves increase efficiency by changing the thermal mass potential. The air in contact with the surface of the radiator is were that transfer happens. Increasing air flow over that surface does not necessarily improve the transfer of energy. The common portable heatpumps take in air, the heat energy is transferred, the air is exhausted. Changing that to one were the air flows constantly through that exchange might result in the coil icing over.

[@dansynth8408]

I'm not sure the compartment needs to be airtight...it might not be as efficient but just attaching a hose down there will work on the principle of least resistance (assuming the rest of the grill is blocked, which can be done without opening the cabinet)

[@socks2441]

its easier for the air to be pulled in from other areas and gaps in the unit, sucking air in from the room than it is to suck all that air down a long small hose from outside, so you do need to seal it inside at least to some extent. it depends on the unit though, i have heard some are already well sealed inside so can be converted to dual hose without pulling it apart. you can test by blocking off the intake grill. if that pretty much stops any exhaust air, it is sealed inisde, if it doesnt, you will need to seal it yourself before converting to dual hose. i saw a video where a guy converted to dual hose without sealing the unit and his efficency actually decreased, because it sucked the cooled air from the top back down to the bottom, making the unit pretty much pointless.

[@dherrendoerfer]

Agreed 100%

[@jammi__]

@@socks2441 Not really though, when the "sucking from the room" means it'd have to pull a vacuum on the apartment and letting air in from any tiny crevices that aren't properly insulated. It's much easier to pull from the hose, since the air pressure outside is going to be higher. Then again, that might be up to your building standards, but at least here in Finland, when you operate a single hose unit, the vacuum in the apartment becomes very noticeable especially when operating doors.

[@RXSVN_2]

27:51 What is that rectangular green thing in the middle of the top vent in the back? Is it some type of special filter? And if it is what is it called?

[@dherrendoerfer]

I think it's a service indicator, it's a piece os colored paper/cardboard, that will probably loose it's color over time to indicate wear.

[@RXSVN_2]

@@dherrendoerfer After asking the question, I looked up a similar air conditioner that had that same thing stuck in the middle once you remove the main filter. It appears to be a anti-microbial filter of some sort. The closest name I could find is what is called a "catechin filter". So it may need to be replaced after while.

[@dherrendoerfer]

Thanks for the update, I did not know that. I've only observed that they tend to go white or grey after a long time.. That's probably when they need to be replaced. But it would make sense to have a mold inhibitor there.

[@decat7485]

I have noticed with my single hose unit the. Compressor gets pretty hot. I would think a second hose with even warmer air from outside might cause the compressor to get even hotter and shut down

[@dherrendoerfer]

The compressor gets as hot as the coolant does. But they usually don't really mind. They have a trip sensor and will switch off if they go too hot. It's never happened to me on this unit.

[@arfiansyah8718]

@@dherrendoerfer Just to share I use to have a portable aircon 12k btu single hose. It didn't make my bedroom very cold even when set to 18 degree Celcius. I tried modding it by adding a second hose it didn't work as.,it was not seperated like in the video. And I find it troublesome as I need to remember how to reassemble it back, in the end I gave the AC to my cousin. So I'm currently using an LG split AC 12k btu works well freezes my room,quite chilly. Do note I'm living in rental flat so yea the landlord gave approval to install. Btw I'm in Asia it gets hot and humid everyday.

[@peppermeat8059]

@@arfiansyah8718 never install an split ac into a rented home! you shouldve just went for an window unit, doesnt matter that its an non invrter, go check out the inverter types, they 30000 zar, believable right? i got hung windows, window ac will not work, split ac can work but installation is too expensive and outside my wall will be terrible, portable ac could work just the efficeincy, noise and power consumption

[@jayakrishnanvg1]

What if you use a 6 inch exhaust fan to suck outside air into your newly installed duct and coupling that fan to run along with the exhast blower in the machine? Such a modification will be bad for the exhaust blower motor?

[@dherrendoerfer]

I don't think it would have a negative impact on the exhaust blower - that said I't perfectly ok with pushing the air the way it is. The slight restriction does not suffocate the blower, its RPM does not change compared to before the mod.

[@chandrathemoon02]

Jay krishna bhai have u tried this. I am planning to buy a 6inch exhaust fan to modify this

[@jayakrishnanvg1]

@@chandrathemoon02 Yes I did, coupled the fresh air fan to the compressor line and it worked perfectly. The issue is faced was that I couldnt properly seal off the evaporator and condensor side and because of that the dust in outside air got mixed with indoor air, I like in a slightly dusty area(during summer).

[@bigbadboogie6842]

30 to 26 = 4 deg original (30? Outside?) 29 to 24 = 5deg final mod (29 outside) = 1 deg difference = 1/4 to 1/5 = 20 to 25% (if not a meassuring error) But outside temp was also higher at orig which makes that test harder. I think you have missed something here. Try fitting a larger diameter hose and seal of wide and narrow fin part kf condenser as wellk 30 to 28 (outside 31) = 2deg initial attempt isnt really relevant

[@dherrendoerfer]

True, yet the final mod had the machine not only reach the 24 but also go into an on/off rhythm of 4/6 minutes. That got lost in editing (my bad). I was planning to have a follow-up video on this and these machines in general, but the weather has not provided the chance to do so, it's turned cold and very rainy. This AC has a stupid flaw/break it can only be operated at 24 or 26C set with the machine ... every other setting will produce random on/off cycles. (That's why it was so cheap)

[@dioclescissoid]

Did you compare the power consumption? Maybe without the pre-cooled air in room, compressor ends up working in more power inefficient mode.

[@dherrendoerfer]

No I didn't - but the thing only has one setting, it's not an inverter-powered unit. I've measured the consumption over the length of a day and it did not vary much.

[@mrm8818]

I hope this guy has taken a lesson in editing after this unabridged shocker

[@wyngreece7]

The only think i want to achieve is to take as much litle air as posible from the room to outside. I dont care about consumption. Is it worth it?

[@dherrendoerfer]

Yes, that will do it - not as well as a split, but if a split is not an option this is a cheap alternative.

[@michael_baron]

Very nice investigation, thank you. :) Did you measure the results in the end?

[@dherrendoerfer]

The improvement in the end was about 160%, It was only measurable by observing a longer period of time than I had done before in the end it settled in to an on/off cycle of about 40 to 60%. also it now reached way lower room temperatures. Sealing off the cavities had the main benefit of keeping outside hot air from seeping into the room.

[@michael_baron]

@@dherrendoerfer Those are great results. Makes me hopeful that I can tackle a used monoblock with some aluminum tape too :) Because I can find nill two-hose systems. Not even new. Midea has a fake two-hose system. It's terrible.

[@cliffbythesea2114]

"For my unit, I had to seal up the area surrounding the compressor and condenser so the air would not get pulled in from the cold side of the device" can you elaborate more. So, on the other side of the condenser that's not the exhaust side, basically tape off all the other walls of the condenser except for the side that's on the same side as the exhaust port?

[@dherrendoerfer]

Both the hot and cold side have an intake and an exhaust. For the cold side the intake and exhaust have a cowling that connects and isolates them to the case and from the inside. The hot side however will draw air from wherever it can and push it out through the hose at the back. So just fitting an intake hose to the back didn't stop the device from pulling in lots of air from the surrounding area. Only when the intake area was isolated from the rest of the device as well did it do a proper job of using outside air to service the hot condenser and not pull from the evaporator side as well.

[@TanCh-dg6lz]

I repeated your test. I confirmed your result. I simple connected an air feeding pipe without modifying Aircon. Its power consumption remain the same with or without the air pipe. BTW, how does your modified aircon working now?

[@dherrendoerfer]

I'm very happy with the updated aircon now, it's been working fine for me ever since - I would put the the improvement at about 160% of what it was before.

[@user-yl5zv5nh3i]

if you spray water on condenser coil or evaporator will increase efficiency?

[@dherrendoerfer]

This unit already uses the condensate from the evaporator to improve the cooling of the condenser slightly.

[@esqueue]

My only experience with a dual hose system actually still sucked in quite a bit of room air and exhausted it. The dual hose setup was completely pointless. I believe that you will not provide enough cool air to the condenser, and it will perform the same or worse than it did when you had a single hose setup.

[@dherrendoerfer]

It did improve the device a lot, but the cooler itself was already (at least partially ) constructed in a way to support the upgrade. I'm quite happy with it now.

[@esqueue]

@@dherrendoerfer Ah, my guess was wrong. 😅

[@chrischoy9]

@@esqueue Can confirm here that it works extremely well. Went from hardly cooling the room to being fairly cool (You know that feeling you get with a high street department stores during summer when the cold air rushes out as the door opens?).

[@therusstm]

Why did you put the modified hose on the bottom right? Maybe I'm mistaken. But the air gets taken in from the giant square at the top not the small rectangle at the bottom right?

[@elbigotesdelatienda]

You're not just mistaken, you're clueless.

[@peppermeat8059]

the top is the cold air bottom is hot air

[@MatthewEng2593]

you say insulation when you mean seal. good video tho. just being picky. thanks

[@dherrendoerfer]

My bad! Insulation,isolation,seal .... the way worst braintwister for german to english thinking ... honestly !

[@3rdeyewatcher]

@@dherrendoerfer So you could put insulation on the inside of the covering/shell also to increase a seal a maintain air temperature???

[@jamescrook99]

Surely you need a gap on the intake reducer before stepping down/up sizes ? Big clive had a video about making a small PC fan filter, he had less flow the closer the step down was to the fan blades themselves

[@dherrendoerfer]

No, the fan in the unit is a squirrel-cage turbine fan, that basically provides its own equalisation zone. It's located behind the condenser with an adequate amount of air volume. The same is true for the inlet, with only the downside that there's a constriction where the inlet grill is/was.

[@jamescrook99]

@@dherrendoerfer thanks, I'm now about half way through the video, I should stop commenting before watching the whole video ...

[@rickl6697]

You have a 3d printer? Why didn't you print a cowl that would incase the entirety of the condenser intake instead of making one that basically cut the intake area by 50 - 60%. The intake coweling needs to be deep enough to gives the air coming in access to the entire intake grille. You covered it up with tape. Air like water will take the path of least resistance. You also need a larger diameter hose. When you did your first test as a single hose you didn't take into account that while you were cooling the room the unit was in, all over the rest of your house hot outside air was coming in through every crack under doors, windows, light switches, light fixtures etc. So the single hose is not as efficient as it may have seemed, unless you had your door taped and sealed up so that any replacement air would enter your house via the same room the unit is in.

[@Stacy_Smith]

For those of you that doesn't have access to a 3D printer, CHECK OUT THIS VIDEO: kzbin.info/www/bejne/opvYqoyNi7B1iJI

[@peppermeat8059]

@@Stacy_Smith ok my bad, but i would expand hose space and make hose bigger,

[@djmystery7235]

So basically two options, insulate and seal off the inside of the machine by yourself or seperste the hot side and hang it out of your window 😂

[@dherrendoerfer]

That's the gist of it - or put the AC outside and just route the cool-air hose.

[@AdmiralValdemar]

@@dherrendoerfer I've just ordered an Amazon Basics unit (I'm in the UK and we finally had this "summer" thing you guys get elsewhere). Anyway, I've been anally going over every permutation of what to do to enhance their lack of efficiency. Since I'm not forking out for a window split unit given the cost, but also since I, too, watched the Technology Connections video a while back and am aware of their thermodynamic shortcomings, I was thinking about doing the dual hose hack too. But then I considered "why not just put the heat producing unit outside and vent the coolness inside?", and lo and behold, others mentioned that too. So, assuming it isn't raining (my county in England is in historic drought right now), this could be a better and simpler solution, no? I was going to put it out on a patio and have a jury rigged adapter to the hose go over the top of the machine to vent the cold air in a bedroom window and have it circulate around my bungalow that way.

[@dherrendoerfer]

Yes, that's an alternative. the only downside is that you lose the ability to control the temperature, as you can't (or shouldn't) just turn the unit on and of using the plug power. The weather's same here in Germany - we have summers, but this is too much for me, and local nature in general. Just make sure that when you use the cold air, that all escaping air is at the top of the room, so you make use of the temperature stacking nature of the air.

[@TechnkLnl]

Isn't it easier to just connect a hose on the part that's blowing out the cold air. Route the hose to the room you would like to cool and put the unit in another room with a window slightly open?

[@dherrendoerfer]

I think it would work, yes. But it would not be able to cool the air again over and over as you can with a true split. You'd get just one pass through the machine, that's all. There are some devices that work just like that.

[@elbigotesdelatienda]

@@dherrendoerfer also it would be running all the time, as the temp sensor would be on the other room... 😋

[@Reneeberry28]

Um the bottom is likely the dehumidifier and the top is where it takes air in?

[@krisskokaramitev4789]

Is that effective in heating mode

[@dherrendoerfer]

These units do not have a heat-pump (reversing) heating mode - but still if it had, it would improve it.

[@MisterJoah]

You could put the AC outside and the hot air hose inside tho 😂

[@rcinfla9017]

Pretty poor design, even for a cheap single exhaust hose unit. Compressor gets most of its cooling from the return refrigerant from suction line so having it on the condenser air input side does little to cool the compressor. You can put a blanket around the compressor and it will not change the compressor temperature significantly. Air flow cooling on the limited surface area of compressor is minor compared to the heat generated by refrigerant compression in the compressor. Cool refrigerant gas return bathing the motor at the bottom of compressor is the primary cooling of compressor. The compressor case heat will raise condenser intake air temperature which will reduce the efficiency. Compressor, clear to the exposed intake grill on backside also allows more compressor noise to escape from intake grill making the unit noisier.

[@dherrendoerfer]

Good summary. Many PACs even have the compressor behind the condenser worsening the situation. Fortunately most of the heat transfer comes from the phase change, and the units have enough refrigerant load to cope.

[@jabbasjz6753]

Smart of you to notice that. I just bought a single hose unit and it is basically 1:1 to the one shown in the video albeit being different brand. My unit has the compressor wrapped in a foam insulation, kept together with velcro.

[@moosenbeans903]

You think like me so yeah but I don't talk that much so Boi. AM I bitching no cause the info is free. Thank you

[@bigbadboogie6842]

Stopped @3:30 There ia one more thing to consider than just the inlet. Behind the plastic shroud, the inlet area is often NOT sealed well. This means that even with a hose to the outside, it will still suck room air (and even mix room air with otuside air a bit = heating). Air always takes the easiest path so a long thin hose with a very leaky shroud vs cokpartment means less efficiency increase..i sealed mine off before buying a hose and will get a box as well as my inlet goes around the corner covering two sides. Also consider FILTER as you will suck dirty air through the evaporator fins = the will get dirty and loose efficiency if no filter especially if outside air is polluted or dusty. Sooo let's keep in watching...i know it works, but fun to see if i can get some additional ideas here

[@Stacy_Smith]

Metal tape and a filter media on the intake works. For those of you that doesn't have access to a 3D printer, CHECK OUT THIS VIDEO: kzbin.info/www/bejne/opvYqoyNi7B1iJI

[@jammi__]

These are regardless always more efficient than letting the single hose unit draw a vacuum in the apartment that forces hot outdoors air in from whichever crevice it can be pulled through, and then mixing with the cooled air. That's why a dual hose unit will have an easier time to pull air from the hose that has the other end in the higher pressure outdoor air than the lower pressure indoors air.

[@GuillermoMartinez-ic9rk]

So is it good or not if it sucks air from the inside of the room?

[@dherrendoerfer]

in short: No if you can pull the air from a cold basement or other cool rooms, then it might not be so bad.

[@akuluarabadunyaasi]

Diyelim ki oda içindeki 100 hacimli hava aldı cihaz 80 hacmi soğutarak odaya verdi ve 20 hacimli havayı aşırı sıcak bir şekilde egzoz olarak yüksek sıcaklıkta dışarıya verdi. Böylece hem odadaki sıcak hava 100 hacimli aspire edilmiş olacak aynı zamanda içeriye 80 hacimli soğuk hava verilecek. Toplamda 180 birim hava soğumuş olacak, odadaki negatif basınç ile alınacak sıcak hava 20 olacak. Bence amanina uygun olarak üretilen bu cihazları modifiye etmek hiç de mantıklı değil. 200 hacim alınan havanin 20 birimi oda dışından içeriye girmiş olacak. Teknik detayını bilmiyorum ama mantık bunu söylüyor. Modifiye edilmiş hali ile düşünürsek. 100 hacim birimde dışarıdan sıcak hava alınarak odaya 80 birim soğuk hava girecek. Ve 20 birim hacimde dışarıya sıcak egzoz çıkmış olacak diyelim bu seferde odada pozitif basınç oluşup soğuyan hava dışarıya çıkmış olacak bence tek egzoz çıkışlı üretim modeli amacına uygun haraket ediyor... !!!

[@sid2677]

Did it stop the vaccum Inside your room?

[@dherrendoerfer]

Yes it did !

[@sid2677]

@@dherrendoerfer Tq for the info. I'm modifying my one.

[@TheMaelxich]

is that an insignia ac?

[@dherrendoerfer]

It’s a Midea OEM.

[@TheMaelxich]

@@dherrendoerferactually, I just did some research. Midea makes Insignia ACs for Best Buy. Thanks for making this!

[@One-Day-After-Another]

Why would they manufacture more popular one hose models when they could just make them two hose for pretty much the same price while being vastly more energy efficient? Well, isn't that a little bit of a mystery... considering the whole industry is gung ho about the climate and environment.... It's almost like they would RATHER be inefficient.... I really would LOVE to understand

[@dherrendoerfer]

I don't have an answer to that - I suppose it's to keep people unhappy and upgrading constantly. I've been in contact with two manufacturers, and they claim single hose is good enough, dual hose to complicated for the customer. I've been trying to get my hand on a real dual hose unit, but so far to no avail. Also, I've not been able to get a high efficiency low power cooler to test - seems there's also no market for that.

[@One-Day-After-Another]

@@dherrendoerfer I saw a dual hose unit on Home depot's website in the mid 300 dollar range... several on ebay too...but a lot of them on ebay say Ebay reconditioned or remanfactured... maybe be just as good. I dunno

[@Beefnhammer]

I think the air pressure problem is a necessary evil of these portable units. They do the job but they will always be significantly less efficient than windows units. It's an inherent flaw of the design. I bought one for one room of my house that is consistently hotter than all other rooms despite the fact that we have central AC. I have no clue why the central AC just doesn't work in this one room. However In my case, the air pressure issue wasn't a big a deal because the primary source of air coming back into the room to replace the exhaust is cool air from the rest of the house where the central AC works perfectly.

[@mreese8764]

So, put a fan in the window to blow out your, instead using an bc ac

[@randybobandy9828]

What you didn't realize is that sure its taking air from the rest of the house but that means the rest of the house is pulling hot air from outside.

[@peppermeat8059]

window units are way too expensive, and they too aswell as the inverters are like over 1k dollars or more for an inverter! thyre vents aswell

[@Beefnhammer]

@@peppermeat8059 I don't understand. Window units are considerably cheaper than portable units. Inverters on the other hand, are the most expensive of the 3 because they require professional installation, so it's not even the same category anyway.

[@jammi__]

@@Beefnhammer That's entirely up to your market. In other markets, window units are nonexistent, because of different building standards and laws. For instance here in Finland, our typical windows are 2- or 3-panel things with 3 or 4 layers of glass. The windows are very thick, but walls even thicker; typically at least 30cm, but they can often be twice as thick. The ventilation windows are tiny and narrow, just about big enough to replace with an insulated board that has space for an portable unit's hoses. I don't think it'd be even legal to have an aircon unit hanging out from the wall in an apartment building. Then again in independent houses, you'd install a heat pump system anyway, and then then the entire compressor is outdoors and you only have the small coolant hoses going indoors into the hot/cold blower unit. Regardless, over here the single hose units are stupidly bad and everyone notices the vacuum they make indoors, making doors hard to pull open and slamming themselves closed due to the negative air pressure, yet the need for air conditioning due to global warming is so new that we don't even have 2-hose units sold as is due to ignorance on both the seller and buyer sides, and we have to make these dual hose modifications ourself.

[@sangkang6294]

So in another word, single hose design is such that it's a single hose unit. Converting in to a dual hose is going to be a lot more trouble than it is worth. Or rather, leave the unit out side and let it circulate the inside air with hoses.

[@dherrendoerfer]

No, I can't confirm that - if effort is trouble, then maybe, but in the end the little machine went from barely managing to cool a single room to doing it with ease. I think that's worth the effort. So in another word: 'depends'

[@wechselrichterschaltungen]

Hallo Dirk, irgendwas stimmt bei den temperaturen nicht.......sie gaben an......unmodifiziert kühlung von 30 auf 26 grad........modifiziert von kühlung von 30 auf 28 grad??? das wär ja noch schlechter als unmodifiziert........oder müssen es 18 grad sein ? das wär ja wirklich eine supermaschine.........viele grüße walter

[@dherrendoerfer]

Nein, die erste Modifikation hat das Ding tatsaechlich schlechter gemacht .... Erst als ich die 2 Kammern komplett getrennt hatte ging auch der Wirkungsgrad hoch.

[@wechselrichterschaltungen]

anzeige war bei 5: 15

[@wechselrichterschaltungen]

@@dherrendoerfer ok, danke für die info.

[@dherrendoerfer]

Jup. Bei 31:43 kommt das finale Ergebnis.

[@wechselrichterschaltungen]

wie war denn am schluss die temperaturabsenkung im raum?

[@JuanBautista-su3qw]

But aahh

[@TimBee100]

They are really overpriced fans. If you blow air out the exhaust that is 100 degrees and suck in air that is 80 degrees in the incoming air vent, then it must be working to some degree, right?

[@dherrendoerfer]

Well they are definitely better at cooling than a fan, but It's obvious that a lot of performance is sacrificed for some convenience.

[@mreese8764]

If you have good ACs in other rooms you'll not feel how crappy the single hose ones are because they suck in the cold air from those other rooms. Of course those ACs do the actual work

[@peppermeat8059]

@@mreese8764 split ac has alot of disadvantages for me aswell as portable a/c but im considering if i should get one

[@mreese8764]

@@peppermeat8059 get a dual hose if you get one. The single hose makes things worse in my opinion

[@peppermeat8059]

@@mreese8764 oh really? i went to look for them there is either none, all sold out or there are ones that are very expensive but in stock

[@hillppari]

inlet hose is too small you doofus. Bigger the better.

[@Stacy_Smith]

Mine works just fine. For those of you that doesn't have access to a 3D printer, CHECK OUT THIS VIDEO: kzbin.info/www/bejne/opvYqoyNi7B1iJI

[@shatterpointgames]

I can't understand why the intake would need to be bigger than the output can you explain?

[@joew717]

@@shatterpointgames because the output is forced air and the intake is passive air. So the outlet can move the same amount of air through a smaller hose because of the pressure from the fan

[@georgeland9862011]

Video to long

[@Jarrizar]

Watched at 1.75x speed..

[@dherrendoerfer]

Sporty - it probably makes me sound very chipmunky

[@pouriyamousavi6892]

30 Minute Video not useful!

[@marcosscriven]

Sure it could be greatly edited down in length, but it's stil useful.