Portable air conditioners that don't leak

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modhatter

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I'm in a pickle trying to decide what to do. My son's bedroom here in the Nevada desert is the hottest room in the house. It sticks out from the rest of the house so it is exposed on three sides. I have solar screens on his windows, and even bought styro foam 2 inch insulation with reflective foil on one side and closed in his windows from the inside (can't see it from outside as solar screens hide it)

Can't put a window unit in because of HOA and his room is the front of house, so I have two other choices. Cutting a hole in the house inside his closet and sticking in a window unit (but would have to run electric to it from outside) and then if the units dies (as many new ones do these days) a replacement will not likely fit the cut out hole. (besides which he would lose use of half of his closet.

Last option is buying a portable unit. Only problem I fear is the leaking of these units. I have just installed new hardwood floors throughout the house, and sure wouldn't want to have an accident. They have a reputation for leaking.

Anyone use one of these that do not leak? If so what brand is it. Someone on the Las Vegas board recommended a Japanese brand I never heard of (Toyotomi) Problem is there are few places that carry them and getting parts if you need it is a real problem.

By the way, I do have central AC in the house, but his room still gets too hot while the rest of the house is fine.
 
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I would get the duct work checked, make sure there is no leaks. Maybe add more insulation on the run to the problem area. Check the outlet temp at vent in the area. Might can resize the duct run to get more flow the room. Had a similar problem at my parents house, AC unit on one end, bedroom at far opposite end. The cooling was lost from a long duct run through a very hot attic space.

I have heard the ductless AC units are a good solution. May check on these

Wall Mounted 18 - 36,000 BTU Cooling Only - Fujitsu Ductless Mini-Splits
 
Yes, i'm aware of the mini split systems. Just don't want the expense of that. i have just spent a fortune on updating this house, and I am spent.
A good split system installed will run in the $2,000-$2,500 range. I have all ready looked into that. I also had AC company out to look at it. Receiving good flow, just getting to much heat from three exposed sides-one side facing West (in comparison with rest of house)

A common problem here in Vegas in the summer by the way.
 
What about a swamp cooler? Should work well in Vegas.
 
They work up to a point, but not with a central AC unit going in your house.
With swamp coolers you need to open up windows for air flow. Not so good for the rest of your air conditioned house. They also can cool only to a certain point. When it reaches 117 degrees here like it is going to Sunday, the BEST they can do it bring the temp. down to maybe 100.

But when it's only 95 degrees outside, they work great. (provided you have your ac off)
 
We have a portable self evaporative ac that worked fine, never had to dump water. The air in Nevada is a lot less humid than it is in FL. I'd check out the self evaporative units and not rule them out. They noise does take getting used to, they are louder than window mount acs but not by much. We bought ours on craigslist and were happy with it, we gave it away after we moved because it was too small for our bedroom. Ours vented to the outside with a one size fits most window vent that was pretty flimsy and needed additional foam insulation to seal properly.
 
I don't think that the portable AC units necessarily leak, but they do collect condensate that needs to be emptied. That could entail some slopping of water. One alternative would be to put a small condensate pump in the condensate collection pan and run a hose to a window or drain.

Amazon.com: condensate pump
 
Like mentioned, I do not think that you would have problems with a leak since your humidity is so low...

Here in Houston, it can be so humid that it does not evaporate and will spill over at some time... most of the times when our company had a problem with spills, it was because someone did not attaché the pan correctly.... BTW, we bought them with pumps...
 
You could also do like we do with our dog's bowl... Put the unit on a catching mat. You know, a "snow mat for boots" like you'll find in Minnesota. Yeah, I know you are not in MN. But some other mat is probably available at an auto parts store, especially for trunks.

So you get the portable unit. Put it on the mat. That mat is only a backup in case it leaks or condenses.
 
When I lived in England, a friend of mine bought a freestanding portable AC unit. It sat in the middle of his living room. It had a reservoir to contain the condensation. The reservoir was open on top with no drain fitting anywhere and no pump to remove the condensation.
My friend was paranoid about the reservoir overflowing and hand dipped the condensation out. He had studied the instructions that came with the unit and it never mentioned emptying the reservoir.
He finally did an experiment by not dipping the condensation out. It filled up and never overflowed. Not sure how this worked but it did.

Suggest searching what kinds of units are available in the UK and see if they are available in the US. YMMV
 
So, the basic problem is that the place where your thermostat is located (and which controls your central AC) doesn't accurately reflect the temp in your son's room (because it has higher heat gain).

- I would definitely check to assure the ductwork to his room is intact. The "slinky" flexible duct used in modern construction is prone to coming apart, and the workers often do a slipshod job of connecting it. It can also get crushed under things or kinked where it changes direction. You can't tell much from feeling the air come out of the register, the ducts need to be visually inspected. I've lived in Vegas and know about the construction standards there: You particular home might be the exception, but in general the quality of construction was very poor. Check everything.
- Does the room have a sufficient "return route" for the air? There's normally a dedicated grill for this (is it blocked by a dresser?) or (more commonly) there should be a good-sized gap under the door--slightly larger than the area of the registers leading to the room. (Is the gap there? Has higher carpet/thicker carpet pad or a throw rug decreased the area of the gap?)
- Are you running the system fan continuously (rather than just when the AC is cooling?) That will help equalize temps throughout the house, including his room. It does use more electricity and it also increases heat gain if your ductwork is located outside the building envelope (e.g. in the attic), but if this heat problem in his room is just an occassional annoyance on the hottest days, maybe this is the easy solution.
- There are "booster fans" that you can install inline with the duct to his room. They can be thermostatically controlled. When the AC turns on, they will assure the room gets a bigger share of the cooling. That sounds good, but it's not a great answer because his room will just get too cold (when the AC is running) and then too hot (because you've still got the differential heat gain problem). But such a fan could be really useful if you just let it run all the time, so that his room gets a constant supply of (cooler) air from the rest of the house, drawn through the ductwork (and the heated air from his room goes out via the return grill or under the door). But, if your ductwork (insulated or not) runs through a hot attic, this might not work because the relatively slow moving air will pick up tons of heat (the insulation around standard ducts is relatively thin (R-6 to R-10), and if they run through a Las Vegas attic they'll pick up tons of heat). Instead, you could run a very well insulated duct (R-30+) directly to a central part of the house from his room and keep a fan in it going during the hot part of the year. This small fan will cost less to run than running the central AC fan all the time.
- Using your home's existing AC system in the ways above is the preferred solution--and it will also assure his room is warm enough (despite all the exterior walls) in your two week Las Vegas winter. If you don't want to do that, I would suggest instead adding a dedicated wall AC unit in his room rather than using a portable unit or spending for a split system. The portable units still need to have a vent to the outside (to dump the heat) and the ongoing problem of getting rid of condensation. And they take up floor space. Since the room has exterior walls, just make a hole in one of them and install an AC unit. It won't have to be big at all, and you can simply use an inexpensive window AC unit (less than $200). Pick a common size and you'll be able to cheaply and easily replace it when it dies in 8-10 years. Slope it properly to the outside and it will never leak into your home. These do make noise, but they aren't as loud as they used to be and your son will probably prefer that to being in a sweltering room. He'll have an independent thermostat so the complaints should stop. You can install it wherever you want on the exterior wall: Below a window or way up high (I like the high option because it's less likely to be in the way of furniture, the unit will constantly be removing the hottest air in the room and returning cool air, and being way up makes it more likely that the unit will be shaded by the eaves of the house, cutting energy use.)
- Obviously, do what you can to reduce heat gain in that room. Shade (trees/bushes/awnings over the windows) can help a lot, and it wouldn't hurt to add more inches of insulation over that room in your attic. If you've got a typical attic this is relatively easy to do and it could make a lot of difference in the heat gain of that room.

Good luck!
 
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Had some wall mounted cooling/heating combo units (in every room) when I lived in Okinawa. They were awesome. It is hot and humid there during the summer and they cooled like crazy.
 
Check for duct flow and adequate return air. Consider planting trees for shade. Also consider using an additional central unit for that room only.
 
I have portable ACs in my house. It get's humid here, and the self-evaporation feature doesn't always work. If the tank fills, the unit shuts off automatically. I was worried about the possibility of leaks, or spillage when emptying the tanks (the drains have a short hose attached that needs to be re-directed to another container to drain the tank, and that container is then emptied).
I placed each unit on a large tray purchased from a restaurant supply store, and no longer worry about leaks or spillage.
 
I have been using a Portable AC unit in my bedroom for many years, to save on using the central system.

Since Northern California humidity is low, I have never had a problem with the water. I empty out the container each evening before turning on the unit. there is usually only a minimal amount anyway.

My unit is a Delonghi Penguino, of 10,000 BTU rating. I am happy with it.
 
In addition to all the good info here, esp the detailed response from samclem, there is one more option.

On a recent 'This Old House', they replaced the standard thermostat with a controller and wireless remote thermostat. You can then put the wireless thermostat module in that far room, to keep it more comfortable.

That will tend to make the rest of the house cooler than you want - but maybe not so bad, as the circulation will help even things out. Pay special attention to the ducting, supply and return (as others mentioned). And when that room is not in use, you can move the module back near the original location.

I'm considering this for our house for nights when we need the A/C for the humidity, but the temperature is not so high. On those nights, the cool air settles to keep the downstairs thermostat cool, so the A/C doesn't run much. But the hot air keeps rising to our upstairs bedrooms. Sometimes I keep the blower on overnight, but I think this would be better.

-ERD50
 
modhatter said:
I'm in a pickle trying to decide what to do. My son's bedroom here in the Nevada desert is the hottest room in the house. It sticks out from the rest of the house so it is exposed on three sides. I have solar screens on his windows, and even bought styro foam 2 inch insulation with reflective foil on one side and closed in his windows from the inside (can't see it from outside as solar screens hide it)

Can't put a window unit in because of HOA and his room is the front of house, so I have two other choices. Cutting a hole in the house inside his closet and sticking in a window unit (but would have to run electric to it from outside) and then if the units dies (as many new ones do these days) a replacement will not likely fit the cut out hole. (besides which he would lose use of half of his closet.

Last option is buying a portable unit. Only problem I fear is the leaking of these units. I have just installed new hardwood floors throughout the house, and sure wouldn't want to have an accident. They have a reputation for leaking.

Anyone use one of these that do not leak? If so what brand is it. Someone on the Las Vegas board recommended a Japanese brand I never heard of (Toyotomi) Problem is there are few places that carry them and getting parts if you need it is a real problem.

By the way, I do have central AC in the house, but his room still gets too hot while the rest of the house is fine.
Click to expand...

I am a mechanical design (HVAC and plumbing) Professional Engineer. I'll give you some free advice.

DO NOT buy a portable unit. You will regret it. How will you get rid of the condensate, do you really want that big thing taking up valuable floor space, and more importantly, how will you duct away the rejected heat? If you can't answer the third one, you are just playing shuffleboard with the heat.

Buy what is called a "ductless split system". Only the DX (direct expansion) refrigerant pipe is piped outside to an exterior condensing unit that can be placed anywhere other than the front of your house and make the HOA happy. The heat is all carried away by the DX pipe. The interior portion of the "split" system is installed in your sons room. They come in half ton and 3/4 ton sizes and are made by Sanyo, Toshiba, and I believe also now Carrier and some others.
 
I can't comment on the portable AC, however I had a similar problem in our master bedroom. This room was always several degrees warmer than the rest of the house. In addition to the ceiling fan we would also run a floor fan to keep us cool. My DW and I always complained about it up until last month when we replaced the AC units and had the ac guy add another vent in our room. It has made a huge difference in our room. We sure do wish we had done that years ago.
 
Al in Ohio said:
I am a mechanical design (HVAC and plumbing) Professional Engineer. I'll give you some free advice.

DO NOT buy a portable unit. You will regret it. How will you get rid of the condensate, do you really want that big thing taking up valuable floor space, and more importantly, how will you duct away the rejected heat? If you can't answer the third one, you are just playing shuffleboard with the heat.

Buy what is called a "ductless split system". Only the DX (direct expansion) refrigerant pipe is piped outside to an exterior condensing unit that can be placed anywhere other than the front of your house and make the HOA happy. The heat is all carried away by the DX pipe. The interior portion of the "split" system is installed in your sons room. They come in half ton and 3/4 ton sizes and are made by Sanyo, Toshiba, and I believe also now Carrier and some others.
Click to expand...

Al, the split systems rock. Problem is the OP said they didn't want to spend that kind of money.

I could see a portable being useful for super-peak days like Las Vegas is having right now. Maybe a few weeks a year. Solves a problem without the cost or installation hassles.

I say if OP is worried about leaks, put it on a tray or mat. Maybe save up for a future real solution like a Mr. Slim.
 
In my humble opinion the OP should bite the bullet and buy the ductless mini-split. He won't be sorry after he gets over the initial sticker shock.

I have a ductless mini-split heat pump with supplemental resistance heating in addition to a conventional A/C system. I live in a very hot and humid place.
 
travelover said:
If you are handy, you can install a mini spit yourself - they come pre-charged.

Example: Comfort-Aire SMA12SC-0 12,000 BTU Cooling (1 Ton), 13 SEER Cooling Only (Air Conditioner) Single-Zone Mini-Split System, 115 Volts, R-410A Refrigerant
Click to expand...
Good idea. I bought my furnace from that company and installed it myself, it works great and saved us a lot of money.

For a DIY option, the mini-split might be easier than the through-the wall AC unit I suggested: No need to frame and trim a new big hole in the wall, just drill a hole or two through the wall for the in/out refrigerant lines and the condensate drain, mount the inner and outer units, and you are good to go. Bringing electricity to the outside unit and the inside one might be the biggest hassle (the through-the-wall unit would simply plug in to an existing outlet unless you go with a monster unit.)

Higher equipment cost for the split system, and when it breaks you'd need to fix it (vs just buying a new one for less than the cost of a service call). But the split system would be quieter and better looking.

Bonus: When your >main< AC unit dies someday, having a room with independent cooling is going to seem like a very nice thing until you can get the main one fixed. "Son, you've got some roommates."
 
Samclem made excellent points.

1. Go to an AC forum and see what they would suggest.
2. Install a return for that room. A return ductwork might not seem like a big deal, but it's huge. That alone might solve the problem.
3. Add extra insulation in the attic above his room. That again is a big factor.
4. Check his run, ductwork from furnace to his bedroom. Make sure as straight as possible, large enough duct for such a long run and most important, no leaks. (When ductwork has bends in them, it cuts down on the flow tremendously.)

If you go to an AC forum, there will be so many ideas, it will become dizzying. But if you do points 2, 3 and 4, I don't think you'll have any more problems.
 
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