Air conditioning

ingenious

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With the incredibly hot weather of the past few week or so, I’ve been thinking about the possibility of fitting aircon on the boat.
Coincidentally I finally managed to get AC electrical schematics of the boat from the Jeanneau owners group - there were only drawings of the DC side on the printed manual I got and Jeanneau haven’t responded yet. This shows the Aircon option with one in the main cabin and one in the helm area. They work by exchanging to seawater rather than to air as per this.

image3.jpeg

It seems they have a dedicated shore line and/or bigger generator to run them.

image2.jpeg

On my boat the items with C prefix in this drawing don’t exist and the right side of the switch control panel (A55) isn’t populated.
So: Is it worth getting someone to quote to replicate this sort of system or am I better looking at ones that vent to air? I’d be fitting in both cabins rather than helm area.
What sort of size (BTU) are needed to cool the cabins on a smallish (11 metre) boat?
This would be a project for next year, to fit over winter, I’m off the boat for a month now and, when I get back I’m going to head further North, up to Bordeaux and thereabouts rather than back to the med which I will return to in late Sept/Oct.
 
I am looking at fitting from scratch on a 13m boat. I have a 12000 BTU portable in the salon and it just about copes at 30 degrees. I’d go for a 16000 for the small difference in price, with a 9000 in the cabin. I think the small self contained units are best for this size of boat with ideally an inverter control for the compressor. You need to fit a water inlet and pump and an external pump out above the water line and pipework.You need a generator if you’re using this off shore power. A 12000 BTU unit takes about 1100 watts at full power do a 4kw generator will run 2 units ok. I haven’t considered a big lithium bank as I have a generator already. They cost £3700-4500 each in uk depending on size/ model. I’d be doing the install myself
 
I have a compact 8000 btu portable unit with venting hose out of a porthole . After purchasing an insultion hose for the exhaust vent and some work to make the exhaust exactly fit the porthole it does an amazing job for a tiny fraction of costs what a marine aircondition would come . With a generator onboard i can run it even underway .
 
I modified my water outlet to outlet through the hull bottom. Having a 11m boat in the Med most of my neighbours didn’t have a/c so a constant stream of water all night while struggling with heat is something they really don’t need.
I didn’t perceive any drop in performance.
I know you are going to say how do you know the pump is working but I had a glass top filter so could see it on startup and after that no more observation needed (you wouldn’t constantly monitor an above the waterline anyway)
Just saying
 
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I modified my water outlet to outlet through the hull bottom. Having a 11m boat in the Med most of my neighbours didn’t have a/c so a constant stream of water all night while struggling with heat is something they really don’t need.
I didn’t perceive any drop in performance.
I know you are going to say how do you know the pump is working but I had a glass top filter so could see it on startup and after that no more observation needed (you wouldn’t constantly monitor an above the waterline anyway)
Just saying
I agree that being next to a boat with the aircon constantly pouring water can make sleeping almost impossible....what is worse is that they are reverse cycle so do it all winter as well
 
I am looking at fitting from scratch on a 13m boat. I have a 12000 BTU portable in the salon and it just about copes at 30 degrees. I’d go for a 16000 for the small difference in price, with a 9000 in the cabin. I think the small self contained units are best for this size of boat with ideally an inverter control for the compressor. You need to fit a water inlet and pump and an external pump out above the water line and pipework.You need a generator if you’re using this off shore power. A 12000 BTU unit takes about 1100 watts at full power do a 4kw generator will run 2 units ok. I haven’t considered a big lithium bank as I have a generator already. They cost £3700-4500 each in uk depending on size/ model. I’d be doing the install myself
Can you give me a link for these units please
 
I am looking at fitting from scratch on a 13m boat. I have a 12000 BTU portable in the salon and it just about copes at 30 degrees. I’d go for a 16000 for the small difference in price, with a 9000 in the cabin. I think the small self contained units are best for this size of boat with ideally an inverter control for the compressor. You need to fit a water inlet and pump and an external pump out above the water line and pipework.You need a generator if you’re using this off shore power. A 12000 BTU unit takes about 1100 watts at full power do a 4kw generator will run 2 units ok. I haven’t considered a big lithium bank as I have a generator already. They cost £3700-4500 each in uk depending on size/ model. I’d be doing the install myself
Thanks for this.
I don't really need in the salon/helm area as the combination of the rear opening doors, the side door and the sunroof gives fair airflow. So maybe 2 x 9000 in cabins.
I have a 5.5kw Parugo generator. Interestingly enough the drawings seem to indicate you need > 7kw to run the Aircon off generator

IMG_4738.jpeg
 
The 10000BTU version linked to above draws 2.9 A at 230 volts so 2 units would be 5.8A or 1350 watts. They are inverter controlled so soft start. My 4kva generator 3,6kw runs the portable unit and a kettle and still is showing half load. I suspect that the generator is oversized to allow for the high start current on older AC units.
 
In my opinion in the south of France in the Mediterranean in summer you only need air conditioning in port…unless there is a lot of mosquitos about (which does happen)…because there is always sufficient air flow to stay cool.
In port is a different matter…it can be extremely stuffy and hot…also you might need to seal up the boat because of insects and noise.
But the length of time during the year where air conditioning is desirable and a fan can no longer cope is quite short.
Obviously those that are further south or who live on the boat full time through out the season will have a different assessment.
This means that while an air conditioner is desirable, I am extremely price sensitive about the investment
 
I have a compact 8000 btu portable unit with venting hose out of a porthole . After purchasing an insultion hose for the exhaust vent and some work to make the exhaust exactly fit the porthole it does an amazing job for a tiny fraction of costs what a marine aircondition would come . With a generator onboard i can run it even underway .
I can see that working in the side cabin where there is an opening porthole and a convenient shelf to put it on but the only vent in the main cabin is the roof/emergency exit hatch.

IMG_4749.jpg
I’m told that those with mid cabins might have a different experience.
But I think that the OP has a small boat like mine
Yes, 11M motor cruiser, Jeanneau NC11
 
I fitted a water cooled true aircon when the cooling water circulated through an external tank below the water line so no noise outside.

My unites were designed and used in shopping centers where air cooled units are not easy
 
I fitted a water cooled true aircon when the cooling water circulated through an external tank below the water line so no noise outside.

My unites were designed and used in shopping centers where air cooled units are not easy
Can you explain in more detail…next week it’s forecast to be 36c
 
Can you explain in more detail…next week it’s forecast to be 36c

I have 3 separate air cons which the condenser is water cooled.

I have a steel boat so used a rudder skeg as a heat exchanger that the water from the condenser was pumped around the condensers and then through the sked / external tank using a mains pump controlled with valves and a set of relays to control the pump.

Th air com is powered by shore power only buy could be powered by a generator but not required when sailing but on a power a different matter

Condenser unit

evaporator unit


Low speed fan for lower noise
 
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I'm also have an 11m old sport cruiser type of boat.
my situation is that I have nothing, no lithium, no aircon, no genset. also thinking which path to take for an A/C unit.
main usecase would be to use it at the marina so having shorepower. but occasional anchorings would also be a bonus. but got interested in the new DC units anyone has experience with those? I guess with a bigger lithium battery bank you could cover one night with A/C, but maybe that's the most, you'd need a lot of solar to recharge... so in the end maybe going with AC powered unit(s) is more simple in the end. and adding a genset later and not messing up with lithium.. difficult choices..

what are your thoughts about DC powered A/Cs?
 
Looking into this atm as well. In our case, there is currently no shoreline power in the small harbor we will spend this summer and we also don't have/ don't want a genset. So thinking of a smaller split unit for camping like the Eurom AC3201E. Boat is a Cranchi Mediterranee 40 and we require this mainly for the nights. Not to transform the boat into a fridge but to ensure a workable temperature around, say, 25°C. For power supply, I will test my Jackery 1000 solar gen this year, although this will likely only suffice for 2-3 hours of cooling. However, using the timer function of the device this may suffice. Anyone else doing it this way? Wdyt of my concept? It's not ideal but can't think of a better way currently...
 
Looking into this atm as well. In our case, there is currently no shoreline power in the small harbor we will spend this summer and we also don't have/ don't want a genset. So thinking of a smaller split unit for camping like the Eurom AC3201E. Boat is a Cranchi Mediterranee 40 and we require this mainly for the nights. Not to transform the boat into a fridge but to ensure a workable temperature around, say, 25°C. For power supply, I will test my Jackery 1000 solar gen this year, although this will likely only suffice for 2-3 hours of cooling. However, using the timer function of the device this may suffice. Anyone else doing it this way? Wdyt of my concept? It's not ideal but can't think of a better way currently...

Interesting unit but make sure you can attach it since your boat does not have windows like a camper but portholes .
 
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