Portable (standing) AC Units - Which brand?

zeehag · Sep 3, 2014

aftermuch research and hemming and hawing 3 1/2 yrs ago in hotville, mazatlan, i bought a window unit t hat drains out onto deck, not inside cabin and does not discharge heat back into boat.
all a/c units make heat. free standing ones as well as window units. the heat has to go somewhere so i chose out the back into the waist of boat.
but then i has formosa windows for one, and it is easy to remove and reinstall.

kito · Sep 3, 2014

down_shift said:
No must have for me, but must have if I want my wife to join me during another hot weekend. Thinking many here can understand that.

Ditto that!. Especially if you was planning on some "V-berth boogie" later on

zeehag · Sep 3, 2014

i bought mine for my cat, who was melting in summer heat....

Bad Obsession · Sep 3, 2014

One of my wife's biggest complaints has always been the heat. She gets migraines from it. I also have a hard time sleeping when the cabin temps are 80 degrees or hotter.

We have been blessed this summer in the Chesapeake Bay region with very mild temps. The cruising here during July and August can be awful and I have even experienced really bad heat in the end of May. When temps get to a certain point I hate going into an anchorage and that usually means I stop cruising for the heat wave.

A lot can be said for cooling the boat down. Some may get use to it but others can be done in by it.

I will eventually go the portable AC route someday.

zeehag · Sep 3, 2014

sorry i forgotto mention the brand nname of the unit i picked up for 140 usd in mazatlan. they sell for 75 usd in usa..is LG, a 5000 btu unit. works well.

philwsailz · Sep 3, 2014

Go see my AC install in my refurb thread in the Catalina Mid-size boats forum.

I am running an 8K BTU window unit in a bulkhead between the cabin and a cockpit lazarette. It drains into a shower sump. Air exchange in the laz is handled by a 95CFM squirrel cafe fan.

It cools my 27 down quick. Even in 120* temps inside my un-insulated shop.

The install cosmetically looks built-in yet without the cost of a marine unit. One bonus: it works on the hard....

philwsailz · Sep 3, 2014

The AC install starts on page 15. Don't get too confused as you read through. I actually installed two units before I was happy. The first unit pointed to a few mechanical issues that needed to be addressed. It was also only 5K BTU.

The second unit proved ideal. It is installed so that condensation drains properly. It is a surprisingly short unit height - wise... It seems height is usually the key dimension to figure out what you can fit. I think the 8K unit I bought is probably the least-tall unit on the market:

http://forums.catalina.sailboatowners.com/showthread.php?t=123450&page=15

jwing · Sep 4, 2014

Speaking from the perspective of an HVAC pro/energy efficiency engineer, I'd say the single-hose portable a/c units are ridiculously bad.

If you must get a portable a/c unit, get a dual hose unit. The brand doesn't matter, most of them are made by the same Chinese outfit and have the same internal machinery with cosmetic covering and a feature or two as specified by the company that owns the brand name.

If you go ahead with a single-hose, well you should get the smallest one they make and minimize your mistake. Put it close enough so that you can feel the cold draft on your skin. Buy earplugs, they are all noisy, even the dual hose units.

Overall, you are better to reduce the heat gain to your boat (shading and ventilation), add fans for air movement (fans actually add a little heat, so turn them off when you are out of their reach), and spend more time on deck. If you still need cooling, the best way to go is water-cooled a/c or heat pump. If you decide on air-cooled, at least use outdoor air as your heat sink, not indoor air like the single hose ripoff units use. Small window units that you can get for cheap are outdoor-air-cooled, less noisy inside, and drain condensate outdoors.

zeehag · Sep 4, 2014

i found my LG brand 5000ntu a/c window unit much more efficient than any built in marine unit i have experienced.
they are also very cost effective.
i live in tropical areas on my boat, and i have found tropical summers require a nice efficient unit. my LG is perfect. i use a fan to move air to other areas of boat and i am most happy. so is bubba daboatkat.
humidity is lowered, and boat is pleasant. i keep it on low settings fro removal of excess water. isnt much needed for temperature as we keep 85-90F year round.

as water temps are also a factor in comfort, an das our water is 85 in winter and 100 in summer, is a necessary item, unless you just love heat and humidity.
keeping sun off decks is most important- you will find with decks covered and coachhouse covered, you will drop interior temps up to 10 degrees. appearance is not a problem, as all boats here cover for summer. (appearance does not make a difference with me--i donot care to look like a snotty richie rich with too much money with shiney boat magnet fro bandidos.)

Benny17441 · Sep 4, 2014

One last final comment, it seems that the larger the boat the better a portable seems to work as they have a larger volume of air to play with. The larger boat can retain a larger volume of already cooled air for much longer. This reduces the effects of the hot humid air creeping back in from the outside. There is one caveat and that is that there will be a larger area of deck and topsides radiating heat to the inside so the maxim that the bigger the boat the more BTU are needed still stands but the unit will work more efficiently in a larger area.

jibes138 · Sep 4, 2014

Benny17441 said:
One last final comment, it seems that the larger the boat the better a portable seems to work as they have a larger volume of air to play with. The larger boat can retain a larger volume of already cooled air for much longer. This reduces the effects of the hot humid air creeping back in from the outside. There is one caveat and that is that there will be a larger area of deck and topsides radiating heat to the inside so the maxim that the bigger the boat the more BTU are needed still stands but the unit will work more efficiently in a larger area.

why not get a unit from an old surplus airplane? Should be light, corrosion resistant and very efficient

zeehag · Sep 4, 2014

Benny17441 said:
One last final comment, it seems that the larger the boat the better a portable seems to work as they have a larger volume of air to play with. The larger boat can retain a larger volume of already cooled air for much longer. This reduces the effects of the hot humid air creeping back in from the outside. There is one caveat and that is that there will be a larger area of deck and topsides radiating heat to the inside so the maxim that the bigger the boat the more BTU are needed still stands but the unit will work more efficiently in a larger area.

one answer for the radiant heat problem--TARP the boat so decks are not in sun.. lol is soo easy, and it works sooo well...

wflowe2 · Sep 4, 2014

In my opinion, and I've tried the free standing unit, it is much better and takes up much less room to get a small window unit, mount a handle on top for ease of carrying, and make temporary hatchboards so you can put it in the companionway. It drains into the cockpit.

Keith13315 · Sep 4, 2014

I have the Cruisair® Air hatch mount to use on the days it is hot and humid at the dock. works well. Both my wife and I think it works well I set it on lo cool and thermostat about mid point once it initially cools down.

MrBee · Sep 5, 2014

We have an Irwin 34 and this is the unit we bought, http://www.bestbuy.com/site/danby-8000-btu-portable-air-conditioner-white/1980337.p?id=1218330802464&skuId=1980337&st=categoryid$abcat0907004&cp=1&lp=3
Its a danby 8000btu. It may be a tad small in BTU but it fits perfect where we wanted to put it. If really hot outside I set it on the counter top next to the sink and stove. It fits there just right. This also has the effect of cooling the air from the very top of the interior down and has worked fine for us. We do close off the V-berth until the cabin gets cool then we open it up again. We run the regular fans to help circulate the cool air. We have our boat in Middle River , Md. This unit is small enough for me to lift it up there when needed and then when going out sailing I set it on the floor in the galley area. It's small enough to be able to work around. If we just need a little cooling for sleeping then I leave it on the floor. I made a plywood vent board to fit our portlight and I just lock that in and run the hose to it. After running for a day I only have about half cup of water to drain and I just pull the unit to the side of the counter and drain into a cup and dump it that way.
For us it was a matter of size,weight and needing to fit where wanted it.

Brian

kito · Sep 5, 2014

I made my plug out of foam. The kind the interlocking floor mats are made of. I am not using the oblong adapter mine came with. I just cut a piece of foam to fit snug in the port with the window open. I then just cut a 4" hole in the foam for the hose to fit in. Friction keeps it in place and seals well. Actually I have 2 hoses in mine..exhaust and inlet.

Ken Cross · Sep 5, 2014

Consumer reports just did a study (for home use) of portable units and if I recall they didn't like any of them and apparently none of them could come close to meeting published specs. I suggest going to the local library and have a look for yourself.
Ken

twdevore · Sep 8, 2014

Great idea Kito. I will do that. The duct tape is a pain and not very "pretty". I did buy the foil covered duct insulation for the exhaust and it really helped.