I'm not familiar with that unit, but I don't think I'd trust it to be quiet. Remember, almost everything which is NOT a mini-split is louder than hades. The evap units on the minis are just about inaudible. What a godsend!
I am always fantasizing about having a energy efficient air conditioner for van life, anyone seen any concepts in tech news or anything?
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Side mount? How could that work 90 degrees tilted? Wouldnt that harm the compressor?
Vigo
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He just means discharging to the side of the RV instead of to the rear.
It's more complicated because you generally wouldn't want to stick half of the window unit out the SIDE of your RV for clearance reasons among others. But if you DONT stick about half the unit outside the wall, the condenser fan's intake side, will be trying to pump your interior air outside, through the condenser (not to mention being a gaping hole in your wall whenever the fan wasn't running). That is bad because it creates a slight negative pressure which encourages outside air to leak into your conditioned space from other areas, which dilutes the cooling effect the AC has because it might be sucking in as much hot air, as it is cooling air in the first place. This is the same problem as 'single hose' portable units. So to have the unit mounted on a side wall of the RV, you have to specifically create an airflow path for the condenser fan to suck outside air into the rv, through your path, across the condenser and back out, without exchanging a bunch of that ambient heat into your interior.
So it's a lot trickier to do it well, than it is to just stick it through the back wall in the conventional fashion.
It's more complicated because you generally wouldn't want to stick half of the window unit out the SIDE of your RV for clearance reasons among others. But if you DONT stick about half the unit outside the wall, the condenser fan's intake side, will be trying to pump your interior air outside, through the condenser (not to mention being a gaping hole in your wall whenever the fan wasn't running). That is bad because it creates a slight negative pressure which encourages outside air to leak into your conditioned space from other areas, which dilutes the cooling effect the AC has because it might be sucking in as much hot air, as it is cooling air in the first place. This is the same problem as 'single hose' portable units. So to have the unit mounted on a side wall of the RV, you have to specifically create an airflow path for the condenser fan to suck outside air into the rv, through your path, across the condenser and back out, without exchanging a bunch of that ambient heat into your interior.
So it's a lot trickier to do it well, than it is to just stick it through the back wall in the conventional fashion.
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Moltensurf
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The 12 V model is less btu.
I was told the unit can be run horizontally, and could be mounted underneath a van
I was told the unit can be run horizontally, and could be mounted underneath a van
Vigo
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So i'm sure something is missing from that post and i don't think i fully understand the ones after it either, but on my Midea when your interior temp is far from what you are requesting it operates in a 'range' based on fan speed. So for example on low fan speed if you are far from the temp setpoint it will do about 400w, on medium about ~550-600, and on high ~700-1000w. As you get closer to the temp setpoint it 'throttles down' the compressor to a low of roughly 120-150w regardless of fan speed, because the difference in fan wattage consumption from low to high is miniscule. So the 'minimum' is basically the same even though the maximums are highly dependent on fan setting. Once you've been at the requested temp for a while it will do one of two things. If you have ECO mode off, it will turn off the compressor and continue to run the fan at the selected setting, use <10w operating this way, and turn compressor back on if temp rises. If you have ECO mode on it will turn off the compressor AND the interior fan, but will then run the interior fan every 10 minutes or so to check if the space needs to be cooled again.
eXodus
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No actually the side mounted window unit is getting it's condenser air from a fridge vent through the roof. No inside air is taken.
Look close at the picture. It's a very nice design. Air comes in from above the ceiling and goes out through the sidewall
Side mounted is the orientation in the RV not the unit itself.
Vigo
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So i haven't looked closely at what you posted, but i can tell you i tried doing that.. and it didn't really work.
So a fridge heats air. Hot air rises. It would be silly to only have a roof vent, and not also have a fresh air inlet somewhere at or below the level of the fridge. My rv fridge has an inlet grate level with it on the outside wall. So it's likely that RV does too, although it may not be RIGHT there, it is probably close. Because if the fridge had a hot air outlet and no cool air inlet, it would be a smaller version of the same problem we were discussing where the only way hot air could escape the rv is to suck outside air into it somewhere else.
But even so, the question becomes.. does the air inlet for the tiny fridge, or even the inlet AND the outlet on the roof which is now 'flowing backwards' because of the condenser fan, have enough combined flow/throughput to support the condenser fan's air flow? In my case i would say it did not. The 5k window unit I used has a 'normal' running consumption of about 400w when compressor is running and it's 'happy'. When i tried it in that location it quickly went to 600w and was still rising when i aborted. If airflow across the condenser is insufficient to exchange enough heat out of it, the temperature of the condenser goes up, which means the 'high side pressure' of the refrigerant system goes up, which means the compressor takes more power to push against it. So at same time it's burning up ~200 extra watts in the compressor, it's also going to be cooling less effectively because it didn't push enough heat OUT of the system to accept a full load of heat back into the refrigerant on the next 'lap' through the system. It'll be using more and doing less. If it continues to run like that, it may eventually trigger the thermal safety switch and stop the compressor for longish periods as well.
I think it CAN be made to work with careful attention to the airflow, and power consumption as an indirect indication of high side pressure/temp (since window units usually don't even have service ports to non-invasively monitor system pressures, the power meter is all you got). But you have to know a fair bit about ac and electricity and a little bit of general physics to MAKE it work well, and if you didn't know all that and installed one that way and it worked well, it would just be getting lucky. I'm not down on the idea, but it's not as easy as it seems, to do it well.
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Moltensurf
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I was thinking about putting one of these in my van, but I didn’t like the fact that the fan stayed on continuously. They have thermostats that you can plug into an outlet; when the temperature is reached the outlet will shut the power off to the unit. If you shut off power to this unit all of the programmed parameters are lost. I found a danby unit that is the same. It functions even after a power loss, and all parameters are stored in a memory board
Moltensurf
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I found this mini split unit on Alibaba. Another guy on the forum has mounted one in his van and says they are good.
The one the guy purchased was an all in one unit. The condenser and the evaporator are mounted on the wall of a van or truck right next to each other. The one I found is a mini split, and can be mounted horizontally. Being that it is a mini split the condenser can be mounted underneath a van if you have the space.
Vigo
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So as far as orientation, it depends on the type of compressor. Most of the compressors for household appliances are basically sitting in an 'oil bath' and 'splash lubing' themselves, and if you run them any other direction they will die early. Automotive style AC compressors, other than some really old ones (york? et al?) are lubricated by oil that is 'blown' around the system by the flow of refrigerant and lubricate themselves the same way a 2-stroke engine does. Those are not AS susceptible to changes in angle. But, there may still be a 'reservoir' of sorts in the system where oil does pool up, and there may be ways to tilt that thing where the compressor can ingest a 'slug' of liquid oil and then try to compress it (LOL & compressor breaks itself). For example on a car system with a fixed orifice tube and an oil accumulator, if you turned the thing precisely upside down it could do that, but when's the last time you turned a car upside down and AC performance was your biggest problem? ? If there is no place in the system where liquid oil pools or puddles, then it shouldn't really matter which way you turn the outside unit as far as the compressor. But airflow through the condenser could be an issue. For example if you have the condenser fan blowing straight down the hot air will want to turn right around and go up and get sucked through the condenser again, so it will be recirculating a lot pre-heated air and operating inefficiently. So airflow is a concern.
But the inside unit probably does need to stay oriented a particular way for the condensation collection/drain system to function as intended.
But the inside unit probably does need to stay oriented a particular way for the condensation collection/drain system to function as intended.
eXodus
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There is no fridge in that RV i posted. They just used the vent cover on the ceiling as air intake for the Window A/C unit.
I agree with the airflow will cause higher energy usage if not correct considered. But that should be easy to calculate. The fridge vent cover hole in the ceiling is 25x6 inch. So we are looking at 150 square inches.
The midea U is 20x13 inches total exterior. So I would assume the condenser coil is probably around 18x 12 which is 216 square inch.
So we are slightly undersized, but not terrible. But to really know we would need to measure all the intake holes at the back of unit and tally their size up. Usually on all window units they are less then the condenser coil size
But even if you go from 400 to 600w. That still half of a conventional RV roof top unit.
You would still win.
I didnt know if I had posted this here or not but I guess I didnt yet. About 6 weeks ago I special ordered from home depot a home window fan called a vornado transom and using some aluminum angle mounted it in the sunroof of my 4th gen honda odyssey.
Now that Ive had time to use it enough to comment I musr say it works amazingly well. It takes seconds to remove or install. It uses just 28 watts on high. If I forget about it and it rains some water will get in the car but the fan is weatherproof. The sunroof only has to stay open about 4".
If its blazing hot outside it wont help alot, but for average sunny summer days when the real issue is heat build up in the car, its amazing. It cools the whole vehicle.
Its $100. Available in white or black if you want a heater instead.
Pics to follow.
Now that Ive had time to use it enough to comment I musr say it works amazingly well. It takes seconds to remove or install. It uses just 28 watts on high. If I forget about it and it rains some water will get in the car but the fan is weatherproof. The sunroof only has to stay open about 4".
If its blazing hot outside it wont help alot, but for average sunny summer days when the real issue is heat build up in the car, its amazing. It cools the whole vehicle.
Its $100. Available in white or black if you want a heater instead.
Pics to follow.
Vornado Transom 26 in. 4-Speeds Window Fan with Remote Control Reversible Exhaust Mode Weather Resistant Case Whole Room FA1-0136-43 - The Home Depot
Transom is the result of a complete re-imagining of what a window fan should be. The air chamber abundantly draws fresh air from the outside in - or reverses electronically to exhaust stale air out. Powerful
www.homedepot.com
Vigo
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That's a nice fan. A little on the pricey side, but im definitely going to keep an eye out for sales or similar lower priced options because i like the form factor of it and would like to use 2 to create 'active air exchange' through my house at certain hours.. thanks for posting it!
I do plan to revisit the idea on my RV at some point, but in my case the space was not conducive to 'doing a good job quickly' and i was trying to get the unit installed before a trip so i had to abort and go the 'conventional' back wall route even though it wasn't my first choice. I have an older RV project (1968 Clark Cortez, 19f long total) that i will 100% do the side wall mounting on, with no rooftop unit at all, and however much work it takes is what it takes because im not gonna put it anyplace else.
On my actual running RV that i use that has the window unit, i still have the rooftop unit in place even though i sort of hate it. I would consider removing it or at least downsizing it to a low-profile 8k btu unit. I would probably 'downcycle' it to the roof of my shipping container storage shed. If im working in there i'll GLADLY pay the 1500w penalty to lessen my suffering.
Well if the fridge is no longer there then that makes things a little easier because then the window unit never has to breathe the fridge's condenser exhaust. I'm not sure what you mean by all the intake holes at the back of the unit, do you mean the 'air inlet holes' on the sides and top of the window unit for the condenser?
I do plan to revisit the idea on my RV at some point, but in my case the space was not conducive to 'doing a good job quickly' and i was trying to get the unit installed before a trip so i had to abort and go the 'conventional' back wall route even though it wasn't my first choice. I have an older RV project (1968 Clark Cortez, 19f long total) that i will 100% do the side wall mounting on, with no rooftop unit at all, and however much work it takes is what it takes because im not gonna put it anyplace else.
On my actual running RV that i use that has the window unit, i still have the rooftop unit in place even though i sort of hate it. I would consider removing it or at least downsizing it to a low-profile 8k btu unit. I would probably 'downcycle' it to the roof of my shipping container storage shed. If im working in there i'll GLADLY pay the 1500w penalty to lessen my suffering.
ANT415
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nice
eXodus
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Correct exactly those:
Those would be the surface the unit is able draw air in. If those are less then the 150 Square inch you get from the fridge vent - there should be only minimal impacts from drawing the air downwards. - it's not that far - we are talking like 3-5 inches of roof thickness.
Vigo
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Got it, yeah i agree with your thought process on that. There would still be an effect if the path for the airflow was really long (like, how big is the opening of your mouth, now breathe through a pipe that size that's 30 ft long, it's noticeable but not harmful) but in the case of it being right there inches away, i agree with you.
On my roof vent which is the discharge from the fridge, the actual hole is fairly large but it has a 'lid' on it that keeps rain from going down it, and the gap between the 'lid' and the air port is pretty short so it does shrink the airflow to be much smaller than what the total size of the hole in the roof is.. but you can fix that by spacing the lid up. Mine was just held on by 4 screws. 4 longer screws and some 'super custom bits of fuel hose' cut to length would space it up and open that gap up enough to flow whatever the hole in the roof was capable of. Just might get in some water if you're in a 'driving rain', rain going sideways kind of situation. I see that type of weather once or twice a year..
On my roof vent which is the discharge from the fridge, the actual hole is fairly large but it has a 'lid' on it that keeps rain from going down it, and the gap between the 'lid' and the air port is pretty short so it does shrink the airflow to be much smaller than what the total size of the hole in the roof is.. but you can fix that by spacing the lid up. Mine was just held on by 4 screws. 4 longer screws and some 'super custom bits of fuel hose' cut to length would space it up and open that gap up enough to flow whatever the hole in the roof was capable of. Just might get in some water if you're in a 'driving rain', rain going sideways kind of situation. I see that type of weather once or twice a year..
eXodus
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there are various makes of Fridge Vent with different designs. You should be able to find one which fits the use case.
The fridge vent is so large because the propane fridge works with convection so you need have to flow a lot of air with low speed to cool the fridge.
I read that the Midea flows about 264 square foot per minute (CFM), but no idea if that is condenser or evaporator - and how to calculate that to a surface unit
should have paid more attention in PhysicsYeah $100 seemed like a lot but the build quality is top notch and its relative complexity might be the reason for the price. See its like one of those tower fans but put on its side, so its like a blower wheel, and around part of the wheel is a baffle or door thats about 1/3 the diameter of the wheel, and moves with its own gear motor which allows the airflow to reverse, and when you shut it off automatically covers the wheel sort of closing it. (Its not airtight but blocks viewing into the room and is probably the basis for their weatherproof claim)That's a nice fan. A little on the pricey side, but im definitely going to keep an eye out for sales or similar lower priced options because i like the form factor of it and would like to use 2 to create 'active air exchange' through my house at certain hours.. thanks for posting it!
Well if the fridge is no longer there then that makes things a little easier because then the window unit never has to breathe the fridge's condenser exhaust. I'm not sure what you mean by all the intake holes at the back of the unit, do you mean the 'air inlet holes' on the sides and top of the window unit for the condenser?
I do plan to revisit the idea on my RV at some point, but in my case the space was not conducive to 'doing a good job quickly' and i was trying to get the unit installed before a trip so i had to abort and go the 'conventional' back wall route even though it wasn't my first choice. I have an older RV project (1968 Clark Cortez, 19f long total) that i will 100% do the side wall mounting on, with no rooftop unit at all, and however much work it takes is what it takes because im not gonna put it anyplace else.
On my actual running RV that i use that has the window unit, i still have the rooftop unit in place even though i sort of hate it. I would consider removing it or at least downsizing it to a low-profile 8k btu unit. I would probably 'downcycle' it to the roof of my shipping container storage shed. If im working in there i'll GLADLY pay the 1500w penalty to lessen my suffering.
I will say if youre considering it for home use the output, as many reviews state, is underwhelming if youve had other (full size, dual) window fans before. (Its more than enough for a minivan) However I think their design focus was on making it quiet, its nearly silent, and if youre using one on intake with another on exhaust it should be adequate. Being a blower rather than an axial fan it makes pressure into a closed space well.
It comes with a remote control and you could switch each unit from exhaust to intake effortlessly, it just rotates the enclosure around the wheel internally.
Vornado products as a whole are above average in quality.
Is heating an issue or are we just dreaming about air conditioning in this post? I just retired two Midea U (8K + 12K) in my tiny house in favor of a lesser efficiency mini-split heat pump. A worthy sacrifice as I had plenty of power in the summer, but was left to chopping wood all winter for heat. What a luxury to not have to deal with lighting fires anymore.
Reason being is that a little known fact is a heat pump generates 3-5x as much heat output in watts vs its consumption, depending on how spendy you are with your inverter and unit choice. You could expect a 6K BTU 41 seer mini-split (cutting edge efficiency) to run roughly 600w full peak, which should be doable with a van-size array but you will need a 220v inverter to pair with it. If you want to stick with 110 and keep your costs reasonable you'll top out around 21seer which is still very do-able.
Sorry to chime in on this so late, but if you're going to go through the hassle of installing an air conditioner why not get a high efficiency heater too?
Reason being is that a little known fact is a heat pump generates 3-5x as much heat output in watts vs its consumption, depending on how spendy you are with your inverter and unit choice. You could expect a 6K BTU 41 seer mini-split (cutting edge efficiency) to run roughly 600w full peak, which should be doable with a van-size array but you will need a 220v inverter to pair with it. If you want to stick with 110 and keep your costs reasonable you'll top out around 21seer which is still very do-able.
Sorry to chime in on this so late, but if you're going to go through the hassle of installing an air conditioner why not get a high efficiency heater too?