Residential A/C in boats?

The friendliest place on the web for anyone who enjoys boating.
If you have answers, please help by responding to the unanswered posts.
See posts with no answers
Nickair

Nickair

Senior Member
Joined
Jan 25, 2015
Messages
253
Location
USA
Does anyone have any experience with a room a/c unit installed in the engine room bulkhead to cool the adjacent cabin area?

windowunit.jpg
 
Last edited:
Those room A/C's need to be installed so that the outside part gets fresh outside air all of the time to cool it's condensing coil. If you mount it so the outside is in an enclosed engine room, that room will get very hot and the A/C will probably shut down or at best stop cooling when the condenser gets too hot.


David
 
You probably would be better served by one of those stand alone units that exhaust outside via a dryer type hose. The fly in that ointment is the hose can't be very long.
 
Don't do it !!

There was once an extensive post (not sure if it was here or some other boating blog) about an owner who installed a window air unit under his flybridge area. He really did a professional job of hiding it and ducting it. It was still a "hack" job.

Nothing "irks" me more than seeing a window air unit hanging out of the side of a boat.
Although the installation you propose would not show from the outside, it wouldn't work. There simply isn't enough air circulation in an engine room.

Bite the bullet and buy and install a heat exchanger.

pete
 
We took a couple of small window shaker AC units, removed the condenser fans, built a tank around the two condensers, plumbed lake water to the tank. Going on seven seasons in Ontario.
 
My rooftop RV unit works well going on 10 years now. Used in saltwater but it's held up great. Don't care for the look of window units but if you're cool when it's hot outside then it's worth it.

Another bonus is you don't have to have another hole in your boat for a thru hull and cleaning dead fish from your intake. I'm strongly considering a minisplit system on my Mainship 34.
 
I use a home window unit on my boat. It is installed in a window opening when needed. Works great, but it is not the most visually appealing setup. The advantage is that when we don't need it, it can be left at home.

On my boat it is only used when the boat is docked or anchored.
 
There are some nice installs of a window units, but not always.

The inside standing units that duct outside can be done nicely too like Jay pointed out.

Household units that don't require water have certain advantages that water cooled units don't, but that comes down to what is practical for you.

Aesthetics should be considered ,but is pretty far down on my list.....depending on your overall plan.
 
jleonard said:
You probably would be better served by one of those stand alone units that exhaust outside via a dryer type hose. The fly in that ointment is the hose can't be very long.
Click to expand...
And the compressor,which can be very noisy, is inside the cabin/room. A split makes more sense(see Simi`s post above). Exhausting a window rattler into the ER, while initially appealing, is the option least likely to succeed.
 
DavidM said:
Those room A/C's need to be installed so that the outside part gets fresh outside air all of the time to cool it's condensing coil. If you mount it so the outside is in an enclosed engine room, that room will get very hot and the A/C will probably shut down or at best stop cooling when the condenser gets too hot.


David
Click to expand...

Thanks David.
Copy on the engine room heat will shut down the AC. I need to think of a way to add fresh air to coil. Would that work?
 
Last edited:
jleonard said:
You probably would be better served by one of those stand alone units that exhaust outside via a dryer type hose. The fly in that ointment is the hose can't be very long.
Click to expand...


I thought of one of those stand alone units, although it takes up precious floor space and not sure how I would secure it. Thanks for the idea Jay.
 
Pete Meisinger said:
Don't do it !!

There was once an extensive post (not sure if it was here or some other boating blog) about an owner who installed a window air unit under his flybridge area. He really did a professional job of hiding it and ducting it. It was still a "hack" job.

Nothing "irks" me more than seeing a window air unit hanging out of the side of a boat.
Although the installation you propose would not show from the outside, it wouldn't work. There simply isn't enough air circulation in an engine room.

Bite the bullet and buy and install a heat exchanger.

pete
Click to expand...

Yes Pete,
I agree and also could not stand window a/c being visible. Was not sure engine room bulkhead would work, even though it would be hidden. Never heard of it done that way, which is why I was asking. I will look into a heat exchanger. Thanks for the help.
 
Last edited:
Stowaway has a good system that works. Now that may work even mounted in an engine room? I never thought of raw water cooling for the A/C unit.
 
Last edited:
I had not thought of a RV rooftop unit. Not sure I have a location for this option. Thanks for the idea Mr Wesson
 
I think the best application is split system, like Simi 60 showed above. Thanks guys. The window ac unit into the engine room bulkhead was a bad idea even though it wouldn’t be seen. The split system heats/cools and is flexible with location.
 
We have a portable A/C in our upstairs bedroom because my 99 year old mother lives with us. If we turn the temperature down enough for us to be comfortable upstairs, she freezes downstairs. The portable we have is extremely quiet and very efficient. It almost isn’t noticeable. One advantage is that during the cooler times in the year we put the portable in the closet and it is completely out of the way. However the mini splits are also very nice. I would have gone with a mini split if I could have found a way to get power to it.
 
Two points not addressed. If one cuts a hole in the engine room bulkhead large enough for a window type A/C, the noise level in the adjacent cabin will increase significantly not to mention the loss of any water tight integrity.
 
Last edited:
Group9 said:
That seems to be the newest and bestest way to do it. No water pumps and hoses to fail and sink your boat.
Click to expand...

That and you can get them for $700 on amazon for a 12,000 BTU inverter 115v. I think you can run multiple handlers off one condenser but I haven't seen that much on the subject.
 
Had it not been there when I bought the boat, I doubt I would have installed this 13.5 KBtu rooftop unit since I have a marine ac unit down in the cabin, but the install was nicely done. The few times I used it while underway on a really hot summer day it was semi effective in reducing the sweat factor.
 

Attachments

  • DSC02710.jpg
    DSC02710.jpg
    70.1 KB · Views: 58
My biggest concern with a split system A/C would be, how long it (outdoor unit) would last being exposed to the salty elements? I guess if you're just cruising inland water ways it may be ok, but if you're on the ocean then I'd think twice.
 
Ralsy said:
My biggest concern with a split system A/C would be, how long it (outdoor unit) would last being exposed to the salty elements? I guess if you're just cruising inland water ways it may be ok, but if you're on the ocean then I'd think twice.
Click to expand...

I'm guessing that even if the outside units only last a couple of years, your overall cost (operation, maintenance, AND replacement) is still going to be less than a marine unit. For some people the ability to run the AC when the boat is not in the water is also a plus.

In most cases AC is not a critical component. If it fails enroute, it is not a life threatening event (except for the admiral wanting to kill you).
 
Quote:
In most cases AC is not a critical component. If it fails enroute, it is not a life threatening event (except for the admiral wanting to kill


Good point and So true!
 
Many boats at anchor become essentially unlivable without both the a/c and genset working. I’ve seen large sport fish chased out of the bahamas in mid summer.
 
I have seen the ones that sit on a hatch opening and they don't look too bad. I don't know about how heavy they are but the ads show two guys carrying it. Also don't know about the noise level. There is one down the pier from me which I have seen used, I'll have to talk to the owner this summer. I have considered one for my "V" berth guests.

pete
 
You could replace the mini-split 5 times for the price of a marine air unit install. If you get 3 years apiece out of them in salt conditions, that's decent bang for the buck.

My guess is they'll go longer than that.
 
I give my rooftop unit a freshwater washdown frequently and pull the cover off once or twice a year to check/correct corrosion. I think it is ten or more years old. The mini-split compressor unit out beside my saltwater front home has survived a few hurricanes and had its feet wet more than once - it is 15 years old. So my guess is that out of the way from a lot of sea spray and reasonably cared for, these things are good for a long time aboard a boat.
 
For those considering free standing units, they come in TWO basic types, and the difference is significant.

One hose. This unit takes inside air to cool the compressed refrigerant and sends that air overboard. (The hot air coming out of the hose). Problem is this air has to be made up for through leaks in the interior with.... outside air. Which is hot. (The reason we're running A/C in the first place. This is not efficient.

Two hose. This unit uses OUTSIDE air to cool the compressed refrigerant and then sends it back out. So, the interior air is circulated through the A/C and cooled and sent back into the interior. There is no exchange of interior air with outside air.

These units are more efficient, and therefore at the same capacity more effective.
 
You must log in or register to reply here.

Similar threads

N
Air conditioning La Paz/Loreto
Replies
9
Views
1K
IRENE
IRENE
N
Marine A/C
Replies
20
Views
2K
Circumnavigator
Circumnavigator
N
Unconventional method to retard marine growth
Replies
9
Views
2K
Lepke
Lepke
B
2005 34 Mainship Trawler Solar installation question
Replies
3
Views
622
Bobw0813
B
O
Wind Generator
Replies
20
Views
2K
Hippocampus
H

Latest posts

Back
Top Bottom