Air conditioning 33 foot boat

Yes hartcjhart similar to what I am using. There is a 'proper' unit sold for camper vans and such. It fits on the roof, I guess it is air cooled like the portable ones but the air flows are all outside with just the cool air being directed down from above.
I am investigating these as well as the ;proper; water cooled 'marine; ones.
 
We have a caravan type unit through the deck above the saloon (42 foot Cat).

Living in the tropics, Cairns Australia, an air con is an essential bit of kit, when in the marina we run it 24/7 and a have a generator when away with guests on board, poor things say are melting.

because of the heavy duty cycle we have to replace the unit about every 3 or 4 years, we did try the marine version but it only lasted 4 and half years so not worth extra expense.

Very nice when sleeping as a lot of the very cold air collects in the hulls.

We are now looking to insulate some areas as it's not always practical to have the full shade covers on.

Good luck and fair winds. :)
 
I have an 'Airforce' unit, for which they sell (apparently) a big plastic funnel which clips over the cooling air intake and permits a hose to be attached and stuck out of the window, hopefully not pointing straight at the existing heat rejection hose.

I wonder if a bit of thin board and a length of hose could not be cobbled together for your unit, assuming it's not available as an accessory?
 
nigelmercier said:
The problem with portable units is that they can't be set to recirculate like split units and the units in a car, they draw in hot air all the time. This makes them very inefficient.
Click to expand...


I have 4 portable units at home and they all recirculate. In fact they cannot draw air from outside. The only air doing outside is the waste hot air.

The aircon units I have fitted to my boat are in fact water cooled units that recirculate fresh water passing through the hollow sked so no sea water passes through the unit its self.

I units are designed to use as separate units in shopping centres with a common water cooler outside where the standard domestic unit waste heat would enter the inside of the shopping centre.

The fan system on mine are much larger than the portable systems I have which cuts down on the noise from the air movement like a normal domestic system.

My units are quite large but I do have a 50ft boat.
 
Rogershaw said:
I have 4 portable units at home and they all recirculate. In fact they cannot draw air from outside. The only air doing outside is the waste hot air.
Click to expand...

Your portable units don't truly recirculate - the waste hot air has to be replaced by hot outside air entering the house. Nigel's examples of split units and car units are truly recirculating.
 
Only to a small degree as the volume of air replaced due to the waste heat air exiting the house is small compared to the air drawn in to the aircon unit from inside the house for subsequent cooling providing the waste heat pipe is fitted correctly.

I also have fixed split aircon units at home and I find no real difference in efficiency when comparing same capacity units.

Simple opening a door or window will let much more hot outside air from outside into a room where we are in summer
 
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Ok let me rephrase that. "They cannot draw air directly from outside", in the same way as a car aircon does.


I have 2 Salton and one DeLonghi well known makes in South Africa and I have never seen that fact of a significant inflow of air into a room, and in my company we used aircon all summer long not just into the odd heatwave.

"I have difficulty shutting the door in my study when the air-con is running" you must have your study sealed almost airtight in that case maybe due to all the draft exclusion you need in the UK winter.

The waste heat air hose on all my aircon's are about 150mm dia and it's the only air that needs to be replaced by any inflow into the room and the flow is quite small so I find it difficult how that could prevent you from closing your study room door. Must be different interpretations of usage or a completely different type of portable aircons
 
Dont quite follow some of this. My portable unit blows out a massive amount of hot air, it has to draw this back into the unit somehow. I close up the cabin when using the A/C and masses of outside air are drawn in through the only open hole ( a 4 inch square vent). I hope to be able to duct this somehow in a more direct path to the ac but the unit is still trying to cool down hot outside air rather than recirculating cooler cabin air.
The split or water cooled units must ( in my opinion) be far more effective than the 'domestic ones'?
 
I still have all accessories including:



Just out of interest I bought a cheap AMcor split portable unit. There are no instructions but printed on the case is an indication that the units can be separated as there are one way valves inside. I didn't test this as I was concerned that this meant just one connection. I now see another ebay add for the same A/C which I copy part of below


-Bracket for wall mounting of condenser

-Spanner for connecting/disconnecting the two units. (There is a non return valve in the pipes so you can disconnect the units without losing gas)
This suggests that you can connect/reconnect at will.

This would make this system much more useable on my boat but I am still concerned following advice on this thread.

-Instruction manual
 
Here are some examples of caravan airconditioners.http://caravansplus.com.au/catalog/index.php?cPath=991_68_184&osCsid=vpsof8o3di2m6q3b3oq3rtkj61 They sit on the roof are low profile and pump cold air into the van while hot air stays outside.
There may be a bit of confusion over aircon types. The evaporative type must be fed with water, increases the humidity and brings ina lot of fresh air from outside which must be exhausted. Not good for boats due to inherent humidity on the water. Very good for desert type environments.
Refrigerating aircon has 2 parts the condensor section gnerating and disipating a lot of heat and the condensor unit getting cold so air is blown over it to provide cold air. The room is usually sealed although some outside aitr can be introduced and cooled.
So as said the condensor unit has a lot of hot air to get rid of and is often noisy due to compressor and cooling fan. Hence in domestic situations these are often separated condensor outside evaporator inside. In times gonme by they were fitted in a window or similar wall opening with the 2 parts in one box but separated by a baffle. Referred around here as window rattlers. The type for caravans in the link above are a variation on this but in a cut out or hatch in the roof.
I note that the caravan types seem to be about double the priice of domestic aircon. The split type being more expensive than window rattlers. There are "portable' split units where connection is by hoses and you need some sort of air tight seal for the hoses to go outside. (and be able to pass one unit through the hatch or window. The domestic split untis mostly require a spacialist to install by evacuating the piping. (gas is providedsealed in the condensor unit).
So we have a conflict as usual of price. Domestic aircon (made in China) is very cheap and good but not suitable for a boat.
An ideal boat system would use as said a water cooler (heat exchanger) for the refrigerant coming out of compressor. The compressor would be in engine bay the evaporator unit connected by pipes would be in saloon. This all would be expensive to buy and install due to low volume production.
I can suggest that water cooling of the condensor is common in USA (never seen in Oz) So if you can find 240v compressor or just a heat exchanger this may be a cheaper way to go. They use gound wate for cooling. I guess sea water will be more corrosive but hopefully fairly resitive to corrosion. Some ground wate rhas a lot of minerals in it. You will still ahve the cost of getting a specialist to evaporate and gas the system.
So maybe OPs temporary lash up is as good as it is going to get for reasonable price. good luck olewill

PS i have proposed on this forum that bilge air may be cooler than cabin air (cooled by water) and by recirculating air through the bilge one might get some useful cooling of cabin. Has anyone tried this? (Is it a daft idea? olewill
 
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Thanks guys.
Nigel.... got my unit on ebay....£60 its back on now as I will look for the same but smaller, there is another on at the moment .... just search AMCOR split unit portable A/C
As I say there is an indication on the back of mine that you can disconnect and reconnect it advises that you are quick when you unscrew the union as there is a valve inside. I guessed that it is a little like a tyre inflator where if you mess about releasing the inflator you can loose air ( refrigerant) If these units can be split then I recon I can use one on my boat, just need something smaller than the 14000 btu unit. ( my 9000btu single unit is OK in my boat )
Olewill ( happy birthday) is right about the big price variation between the domestic and camping market!!
My temporary lash up as he says is ok but a split unit would improve on that and a split unit than can be disconnected would further improve.
Cheers
 
I'm watching your AC project(s) with close attention ... Do please keep posting on your progress. Close to 40°C cabin temperatures in July in northern Italy drove me off my boat early this year. Coupled with windless and humid air conditions, trying to sleep on board lying in a pool of sweat was nigh on impossible. Resorting to cockpit or deck was out of the question if one didn't want to be devoured by mosquitos. I either fit AC or change my otherwise excellent lagoon marina if this climate pattern persists.

But it wasn't just me or my location. Friends in my marina who organised work to take off for four months this year sailed to the Ionian in early June; I almost sailed in company with them but they left in very unstable conditions that, being single-handed, detered me so I chickened out. They called me from Austria half-way through their holiday to say they had flown home due to the heat. They return at the end of September to bring the boat back.
 
hi Barnacle,
I am getting a quote from the guy who sells the 'old model' Dometic units for a proper marine package but I guess it will be quite expensive and being 'floor mounted' getting that cold air upward is an issue. The Amcor unit I have on ebay would be an improvement on the single unit I have currently on the boat. It would be more effective and the outside unit is not so big that I couldn't find an 'out of the way' space for it.
A split unit with the high level interior unit and an external unit that can be detached and stored for sailing would be best which is why I am keen to see if the Amcor unit can really be connected/disconnected as required. Mind you the interior unit is going to weigh 25kg so would have to be securely mounted........wouldn't fancy that flying round the saloon.
You are right about the heat, my missus came out when it was about 36 degrees and says she would have flown back next day without the A/C !!
 
pvb said:
For boat use, you ideally need a seawater-cooled unit. This gets rid of hot air exhaust hoses, and also means that you're not drawing in outside air all the time. By simply recirculating the air in the cabin, the cooling performance is enhanced. You can get a 10,000 or 12,000 BTU unit for less than £1000. They're fairly compact, say 50 x 30 x 35H, so could be built into a cockpit locker. Take a look at www.marineairspares.com for some ideas.
Click to expand...

I would love to know where I can get a marine 12000 BTU, AC for 1000 pounds or less. Thanks for any pointers! But of course I should have read the post properly! thanks, I will be getting one from these guys!!
 
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