Portable Air Conditioner

JESSICA

I need to buy a portable air conditioner.
Does anyone know about an energy efficient model?

mike95490

Re: Portable Air Conditioner

You could check Consumer Reports, they do lots of testing. Also, looking for the efficiency rating, I believe most AC units in the US are required to be labeled.

niel

Re: Portable Air Conditioner

here is a good place to look and not just for your room air conditioner.
http://www.energystar.gov/index.cfm?fuseaction=find_a_product.

it is difficult to find at times, but they do allow you to find products and i went to the page you need for ac.
http://www.energystar.gov/index.cfm?fuseaction=roomac.search_room_air_conditioners

JESSICA

Re: Portable Air Conditioner

Thanks.

I was also looking for some advise based on actual experience.

RandomJoe

Re: Portable Air Conditioner

By "portable" do you mean the standalone rollaround kind that have an exhaust hose that blows hot air out the window? If so, I have a 9000 BTU model that is branded Maytag with a Fedders sticker on the back. Got it at Home Depot a few years ago.

The number one thing I suggest when someone asks about these is to get a model that has TWO ducts on it! The single-duct versions like mine are pulling room air to cool the condenser side of the unit, then blow it outside. Which means hot air from adjacent rooms (or outside) is being pulled in to replace it. Not efficient by any means! The two-duct ones pull air in from outside with one, then blow it back out the other. While my unit works okay, it might as well not have a thermostat because it never shuts off.

As for efficiency, while this thing isn't a high-SEER or anything, I think it does pretty decently. It certainly has some power factor correction in it. The Kill-A-Watt meter indicates a 0.94 power factor, and quite surprising me I was able to run it off my Honda EU2000i generator. The unit pulls around 900W while operating, so convention says I shouldn't be able to get the compressor started with only a 2000W peak generator. It starts instantly and the generator just loads up a bit and carries on fine. I have a mini-split unit that's the same size that won't even try to start, and the generator bogs way down on it.

But then if you meant some other type, never mind!

JESSICA

Re: Portable Air Conditioner

RandomJoe:

Yes "the standalone rollaround kind that have an exhaust hose that blows hot air out the window" is the portable unit I was talking about.

Nevertheless, 900 watts is not what I had in mind when I said "energy efficient"!

Do you, or anyone else, know about an air condictioner, portable or not, that draws LESS than 600 watts?

Thanks again.

Dapdan

Re: Portable Air Conditioner

I have a GE 5500btu window unit that pulls 500+ (actually reading from my killawatt meter) when at max setting. I dont think you are going to find any ac units out there that are rated above 6000btu and using less than 600w at max running setting.

Cheers...
Damani

icarus

Re: Portable Air Conditioner

I think by nature, the portable units are very inefficient. A good window unit would be way more efficient on a per btu basis.

Tony

niel

Re: Portable Air Conditioner

he may be forced into a type other than the standard window units because of window design, this could be as simple as too small of a window or may be one of those types of windows with the little hand crank you have to turn to open it, circa early 1950s i believe.

JESSICA

Re: Portable Air Conditioner

niel wrote: »

he may be forced into a type other than the standard window units because of window design, this could be as simple as too small of a window or may be one of those types of windows with the little hand crank you have to turn to open it, circa early 1950s i believe.

Niel:

Yes, you are right; it is the window with the little hand crank...(though it is not prehistoric). However, I can install a window unit, granted it is a very small one (no more than 16 inches wide).

Anyway, thanks for your suggestions and your time. I appreciate.

One more ?: Are those "inverters a/c" (Daikin, etc. ) as energy efficient as their manufacturer proclaim?

niel

Re: Portable Air Conditioner

jessica,
as far as inverters go they do get to be very efficient when you are talking about the better high end ones and that does depend on the load too. if refering to air conditioner efficiencies i can only go by what the government lists them to be and i can't personally vouch for any in particular.

Dave Angelini

Re: Portable Air Conditioner

The portable in combination with energy efficient requirement is just not realistic at this point. I will say that the variable speed, inverter based "split" units from Sanyo can be set to run on as little as 300 watts up to 1000 watts for a 9,000 BTU unit.

I am running 2 of them now and they are amazing. Offgrid with AC has never been easier. Hats off to Sanyo. Oh, and even more amazing is how quiet these units are. The last window unit I had was so noisy you would not hear that a Bear had come into the garage. The Sanyo is so quiet you forget that it is on.

Dapdan

Re: Portable Air Conditioner

Hey dave,

can you offer more info on that sanyo unit or better still post a link so others can look it up.
8)

Cheers...
Damani

BB.

Re: Portable Air Conditioner

Here is the Sanyo website for their A/C line (I think this is what he is typing about)... This link is to their "single split" systems (note, flash based website--may be a bit much for dial-up users).

-Bill

Dapdan

Re: Portable Air Conditioner

Thanks bill

Cheers...
Damani

n3qik

Re: Portable Air Conditioner

Found this:

http://www.globalindustrial.com/gcs/prod/30127522/i/productInfo.web?utm_source=google_pr&utm_medium=cpc&utm_campaign=AirConditioners--google_pr&infoParam.campaignId=T9F

At 2.1 amps, it's the lowest powered AC I have found.

BB.

Re: Portable Air Conditioner

N3qik,

Do you know anything about this unit?

It appears to be a just dehumidifier with a bypass that allows you to point the intermediate cold air from the evaporator stage out the top of the unit.

We would use "spot A/C" units in offices/labs--but you need, at least, a hot air exhaust hose, typically dumped in the drop ceiling (not sure it was legal wrt fire codes--but was the only handy space to dump the heat).

It would be a stretch (in my humble opinion) to call this an A/C unit. It would just dump the waste heat out the back (I would guess, there is no "rear" shot that I could identify)--so you end up dumping another 240 watts in your living space.

-Bill

n3qik

Re: Portable Air Conditioner

Nope, just found it via Google. Have it bookmarked for further research.

It maybe a modified Dehumidifier, but the lowest power AC/Dehumidifier I found was a 3.3 amp from Lowes. That is now a 4.2 amp unit, cause I brought one and found out the hard way.


Found this info on a mini-split using inverter ( DC compressor ) that is rated at 19 SEER for the 10,000 BTU and 20 SEER for the 12,000 BTU.

http://www.amcorgroupusa.com/mm5/merchant.mvc?Screen=PROD_STATIC&Store_Code=AMCOR&Category_Code=INVERTER

homerramirez

Re: Portable Air Conditioner

Sorry Ken, even if it was an ac, the 500w for 5500btu for the GE is more energy efficient ( 240w for 1000 BTUs it will be 1320w for 5500 BTUs) , Wal-Mart sell the 5500 BTU unit for around 100.00 U.S. dlls.

Air conditioner is hard on solar RE, but as Dapan said, working the unit for 2 hrs. can bring some relief if house is well insulated....;)

LucMan

Re: Portable Air Conditioner

JESSICA wrote: »

Niel:


One more ?: Are those "inverters a/c" (Daikin, etc. ) as energy efficient as their manufacturer proclaim?

Yes they are the most efficient a/c technology available at this time, because of the ability to vary the compressor capacity (speed) to match the load.
For more info check here
http://www.fujitsugeneral.com/wallmounted9-12RLS.htm#features

JESSICA

Re: Portable Air Conditioner

homerramirez wrote: »

Sorry Ken, even if it was an ac, the 500w for 5500btu for the GE is more energy efficient ( 240w for 1000 BTUs it will be 1320w for 5500 BTUs) , Wal-Mart sell the 5500 BTU unit for around 100.00 U.S. dlls.

Air conditioner is hard on solar RE, but as Dapan said, working the unit for 2 hrs. can bring some relief if house is well insulated....;)

ramirez:

Yes, I agree.
There is also a Sears/Kenmore 5,500 btu, 515 watts, for just $99.
I guess it is the same GE under the Kenmore name.

n3qik

Re: Portable Air Conditioner

I was not looking at watts to BTUs. I was looking at just watts. I have a 900 watt array. Looking to use something to dehumidify the basement. Used a 550 Watt AC unit to do that last year. Free from parents. But at 550 watts plus other loads, my system is maxed out at this time of the year. I got the new dehumidifier hoping it was at 380 watts. But that did not turn out as expected, it is at 470 watts. A little better, but in two months, the solar may not run it.

Now I found one at 240 watts, this could give mine and others with smaller arrays some type of AC/humidification.

Yes, if you have a larger than 1000 watt array, then the other systems are better suited.

System2

Re: Portable Air Conditioner

im thanking about getting a chest freezer with a pump and a coil, or you could use a water chiller but the chest freezer is much cheaper. and fill it with gylcol and water and pump the chilled mix throw coils with a fan on it.

from what i have been reading it is better to use water as a heat exchange handler, this way you pull hot air from the room and throw the coils and cycle it back to the room. a temp controller may also be needed so compresser dont burn up on the freezer.

BB.

Re: Portable Air Conditioner

Hmmm... A cheap A/C system?

I wonder what the COP would be... If a typical good A/C system is around 3.5:1 (watts cooling:watts running)--For a small freezer that 100 watt of cooling would be way smaller than the "normal small window" A/C system.

Of course, you can run the freezer 24 hours per day to "pre-cool"--but then you need a storage medium.

Latent heat of freezing water is ~3x10^8 Joules per Cubic meter. Or:

3x10^8 Joule / (60 min * 60 seconds * 1,000 per K) = 83.3 kWhrs per m^3

Say you have a good sized 15 cuft freezer and can get about 10 cuft of water containers in it). 1 cuM = 35.3 cuft:

83.3 kWhrs * 1 cM/35.3 cuft * 10 cuft = 23.6 kWhrs of Ice

If a freezer runs at 3.5:1 and it is 100 watts -- it would take:

23.6 kWhrs / (0.1 kWatts * 3.5:1) = 67.5 hours to freeze solid

You also have to add the ~1kWhr per day that is needed to keep the ice frozen in the freezer too. That would add another 10-20% efficiency loss for the process too.

Perhaps, if you have Time of Use metering with a good sized spread between peak/off peak hours -- making Ice at night and using it during the day will make sense (I believe some commercial building have been looking at this already--if not doing it).

But, a 100-200 Watt freezer is not probably the way to do it--I am not sure that it is cheaper or more efficient that a purpose built system--and in any case, it is pretty small and even cooling 1 room would probably need more (if you live in a hot climate). Let alone the issues of freezing water (expansion) and making the freezer capable of containing glycol, tubing, and the other equipment needed to make the system work.

-Bill