Given the heatwaves many are suffering ... mini AC ?

Refueler

Refueler

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Looking for suggestions chinese - or other ... for a mini ac that could run of 12v / 240v .... for a modest sized 38ft sailboat ...

Not really for on-passage - but when berthed / trying to sleep ...
 
We have a mattress cooler. Uses about 8w. It's an evaporative cooler that we put outside. Flow and return pipes send cooled water to a matrix under the top sheet. Works amazingly well. Mattress Cooler USA. We have been using it with outside air temperatures upto about 35degC. Makes the difference between a good night's sleep and not.
The power to run aircon is significant. If you work on a COP of about 2.5/3:1, which is typical, you need a lot of watts to get even a small cabin cool. A friend has a DC aircon unit on a 40ft cat. He just uses it to cool the sleeping cabin. Even with lithium batteries and 1400w of solar he says it is a serious power hog. The initial load to get the cabin cooled down is the problem. Once it's cool, the power consumption isn't so bad.
If you can run off mains power there are lots to choose from and power consumption is not so critical.
 
We have a similar one the No.1 reviewed. It does provide cooling air but only in the direct path of the vents. Can be quite pleasant but comes nowhere near a proper A/C unit.

We have just returned from a delivery trip to SE Spain, where the temperature was in the high 30s C. A 4000 BTU a/c unit was almost useless, lowering the temperature a little in the saloon but hardly worth the trouble of setting up. A 12,000 BTU unit made life quite comfortable in the saloon after a short time. These were both 230 volt machines. The permanent unit that will be installed for saloon and bedrooms will be 16,000 BTU, 40 ft mobo.
 
Have a watch of Emily and Clarke on YouTube. He made his own and goes into detail on how to best cook some space for comfort. He doesn’t try to cool the whole boat, just enough for a good nights sleep. There are a few videos but this one will get you started.
 
I have a water cooled portable unit near my desk now .... but its quite large .... about 25cm x 25cm x 60cm tall .... uses those blue freezer packs or ice to cool the water - which is pumped through pipes where air flows over ...
Works really well but of course ice / freezer packs soon warm up.
It would work on board - as long as mains 240v available ... but is a bit big ..
 
Afloat in Devon, cabin temp at night is not really a problem to us, we just have lots of airflow.

Keeping the sun off during the day is more of a problem.
Apart from the Med, the only places I've felt too hot afloat after sunset have been a few miles inland up rivers in France.
 
Living on the East coast of Africa I fitted a mains driven water cooled true air conditioner similar to those fatted in shopping centers

Min is a split system which has a water cooled condenser where water is circulated around the skeg on my boat that is cooled by seawater outside the skeg then is pumped around the condenser

Being a domestic system the units are bigger but the sir flow is lower that keeps the noise lower similar to the type used in homes

I don't use it on passage just in dock with shore power.

Works very well.
 
Some years ago I used to have a portable AC unit bought from a trade electrical supplier for my daughter who, at the time, was competing at a high level in dressage. We had a 12 ton horsebox, in which we'd driven to Rome, South of France and many other places competing throughout Europe, she was able to sit quietly before doing her stuff getting herself organised in a cool place while the temp outside was up in the 80's and 90's.
I'm sure they're better now, this was 25 odd years ago, but it was brilliant, although it did need some way of venting to the outside, I eventually put a small round opening portlight in for the exhaust to pass through.
The unit was about the size of a large dehumidifier with a 100mm flexible exhaust tube
 
Nigel you are probably aware of the 2 types of aircon. Both common in Oz. First is evaporative where air is pumped over a wet matrix so evaporation cools the air. The second is a heat pump like a refrigerator and requires that the condenser be cooled by air externally or water. The first type are relatively easy on power needing a fan and a pump. They are fine with dry heat but don't work in humid conditions and in fact increase humidity.
heat pump type use a lot of power. Going on my 1kw a/c at home you would need around 500 w to run a heat pump for a small boat.
then of course there are car aircon units where compressor runs straight of engine. Very powerful but do you want to run the engine all the time. I did see one in USA in a house 30 years ago had a Briggs and Stratton engine running on natural gas driving compressor and fan. Very noisy externally.
So what answer for you. I reckon that the bilges in your boat would be quite cool being in contact with cool water. So a fan system to cycle air through bilges then through cabin might help. Or pump[ sea wate through a car heater matrix to cool air a bit.
But really Nigel before you get organised it will be snowing where you are. I know becuase I have just 4 weeks to get little boat in water for a new season. ol'will
 
Interesting topic .. post #9 shows a guy who's developed a system ... reckons 100A/hr of batts to be enough ...

The Evaporative unit I have near my desk works really well .... but needs ice pack changing frequently ..... its also only 240V ...
The cabin on my 38 - the unit could be used without being in the way.

Thoughts are turning to just moving the air .... such as add on car fan ....
 
geem said:
We have a mattress cooler. Uses about 8w. It's an evaporative cooler that we put outside. Flow and return pipes send cooled water to a matrix under the top sheet. Works amazingly well. Mattress Cooler USA. We have been using it with outside air temperatures upto about 35degC. Makes the difference between a good night's sleep and not.
The power to run aircon is significant. If you work on a COP of about 2.5/3:1, which is typical, you need a lot of watts to get even a small cabin cool. A friend has a DC aircon unit on a 40ft cat. He just uses it to cool the sleeping cabin. Even with lithium batteries and 1400w of solar he says it is a serious power hog. The initial load to get the cabin cooled down is the problem. Once it's cool, the power consumption isn't so bad.
If you can run off mains power there are lots to choose from and power consumption is not so critical.
Click to expand...
Do you have any more details about this unit you have Geem?
 
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