On Air Conditioning...

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GREZ

Member
Joined
Jan 8, 2024
Messages
5
Vessel Name
Slow Groove
Vessel Make
1983 34' Marine Trader DC
I am thinking about a salon ceiling (fly bridge floor) mounted RV type AC. :eek:

No AC now. No generator. Is exterior environment an issue? (a lot of RVs hang out at the beach), do I want another hole in the boat to maintain? Haven't looked at capacities yet. Just thinking... due diligence, if you will.

Anyone done this? Thoughts?
 
The sailboat next to me has a Dometic. It would take up a lot of real estate in your flybridge. Personally, I'm going to add an additional package unit on mine to complement my current one. They don't take up a lot of space and are out of the way. For reference, I'm leaning towards the Wabasto FCF Platinum 16k btu 115v unit, just waiting to pull the trigger.
 
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If I recall, standard RV roof AC take a 14" x 14" hole. If your goal is cost savings, you might save $2k on initial purchase and install compared to a marine reverse cycle. You might want to consider impact on resale. Low cost may be an expensive option when the dust settles.

I know the portable AC units with duct hoses run out a window or door are not as efficient. But may be a good compromise in your situation as you could store it in the off-months.

Good luck with whatever you decide.

Peter
 
.... I know the portable AC units with duct hoses run out a window or door are not as efficient. But may be a good compromise in your situation as you could store it in the off-months...Peter
Portable units are attractive especially on price, but the compressor is in the room with you. They can be very noisy, check noise ratings and choose carefully.
 
I find the Webasto platinum units pretty reasonable in priCE and ease of installation. I don’t like the idea of trying to adapt a RV unit. I feel it’s a short term gain and long term loss. However, if the budget says RV style or nothing then you have your answer.
 
New marine units are under $2k. And they can be installed in salon under a seat. Works for us.
 
Another option would be to use a household style mini split, as that gives you a bit more flexibility to place the outside compressor/condenser unit out of the way at an edge of the flybridge or something.
 
Totally biased opinion, have multiple marine ac units backed up by genset. Basically floating condo.
If you are not considering a generator the unit will only be in use in the slip? No one wants to hear an air cooled unit running at the dock.
Trying to walk around an air cooled RTU on your flybridge will be a PITA it needs to be mounted in open air, under the forward console wont work.
If you install a marine ac it can be installed in the lower area of the boat and be properly ducted to cool the cabins which for comfort is probably more important than the salon.
 
I debated this very concept last year.

La Paz is nice in the winter but brutal in the summer. Little wind and high temperatures.

I can only use my boat as an example, but I installed a 21K BUT unit for the salon, and that is marginal in 100 degrees. The inside of the salon goes to the high 70's in the direct sunlight times of the day.

The pilothouse got a 16K BTU unit, and that works pretty well.

The lower cabins have a 10K BTU unit and that is perfect, as they are out of the sun.

The AC units I bought were Velair brand marine self contained with VFD compressors. All three run just fine on my NL 9KW generator. In real life practice they run a total of around 25 amps most of the time.

I also tinted my windows as my boat has huge windows in the salon and pilothouse. The pilothouse got a lighter tint, and the salon is pretty dramatically tinted. We also used the newer high tech UV blocking tints to provide maximum heat transfer blocking while minimizing the visible light blocking.

I mention this because people under estimate the amount of cooling they need, especially ex sail boat owners, because most trawlers are defined by their large windows.
 
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I mention this because people under estimate the amount of cooling they need, especially ex sail boat owners, because most trawlers are defined by their large windows.

Agreed. Many boats have big single pane windows and not much insulation, so it takes quite a bit to keep things cool in direct sunlight on a hot day. Especially if you're trying to cool it down from already hot and with hot engines under the floor, etc.
 
Two of the advantages of a marine unit over an RV unit are efficiency and output. Marine all in one units are essentially geothermal heat pumps. Simply, in peak summer, at the highest heat of the day, the outside air temperature is hotter than the water the boat is sitting in. During the winter, on the coldest nights, the water is warmer than the outside air temperature. In simple terms, heating and cooling with a heat pump is transferring heat or cold from inside to outside. The cooler the temperature outside is when taking heat out of your boat, the greater the cooling effect inside the boat and if you're paying the electric bill, the more efficient (less expensive) it is. It's more efficient and less expensive to transfer heat to 85 degree water as opposed to 100 degree air.

Ted
 
I understand the efficiency of the marine units, but I have also considered the viability of either an RV type if you had a good location or a 12v mini-split like ambulances and trucks use. Primary interest would be the ability to leave “on” unattended with condensate directly draining overboard. No dealing with condensate water and the worry of any failure in the raw-water plumbing system either plugging up, or flooding the boat. I realize failures are not common, and maintenance helps prevent issues. Just stuff my brain thinks about! :rolleyes:
 
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I am thinking about a salon ceiling (fly bridge floor) mounted RV type AC. :eek:

No AC now. No generator. Is exterior environment an issue? (a lot of RVs hang out at the beach), do I want another hole in the boat to maintain? Haven't looked at capacities yet. Just thinking... due diligence, if you will.

Anyone done this? Thoughts?

Based on my experience with marine AC, and as a former Thermo King truck and trailer refrigeration/AC service manager. Don't go with RV style unit, get a proper "mini-split" if you're trying to avoid plumbing in a marine unit. The mini-split will consume real estate on the flybridge for the outside unit, and I don't have a feel for inside noise. Honestly, I'd take the plunge and install a single-piece marine AC unit. Avoid MarineAire in Ft Lauderdale. The unit I bought from them was faulty out of the box, and they wanted me to pay for the replacement part and shipping. Then when it continued to fail, they told me my warranty was voided (unit was 3.5 months old) and sued me when I pursued satisfaction thru my credit card. This was one of 3 new units I installed from scratch and the only one that had issues. I'd go with Flagship Chillers out of Miami. I can be reached at rwaldrop13@gmail.com if you want advice/suggestions, but in our salon (we had a 54' Hatteras) we ended up putting a 15K BTU portable unit in as a temporary until we recovered from the MarineAire debacle.
 
I have been wondering about the "mini" mini-splits that you see on the back of the cabs on truck tractor units. They run on 12v when the main engine is shut down, so ought to work on battery or an APU. Trying to paste-in a photo here:

https://www.google.com/url?sa=i&url...=2ahUKEwjrtO6kmtmEAxWbjrAFHVxHB-EQjRx6BAgAEBc

Has anyone seen these in a marine application? It's air-to-air, so no through-hulls necessary.

The majority of those have a 7-10 HP diesel engine mounted on the side of the frame. The ones that don't have trouble keeping a 60 sq ft space bellow 80deg. They also use over 400ah in 10 hrs. Won't even begin to get into the corrosion issues you would have. Then the good luck finding a competent service provider.
 
I wouldn't expect corrosion to be an issue for the systems intended for trucks. They spend plenty of time operating on salty roads in the winter, which is no nicer to the units than salt spray would be on a boat.
 
You would be surprised how horrible most systems built for commercial trucks are. The companies believe two things when it come to business we have a captured market and the mega fleets only keep the equipment 3-5 years. Given that most products get designed for a 3yr life cycle. I have 30 yrs as a Mechanic, Driver, and Owner of Class8 trucks. My opinion run from anything built for trucks. I'd go mini split if you where trying to do ac cheap with a self install. But given pricing for a true marine unit, suck it up pay once cry once.
 
When we boated in So California and Arizona it was very difficult to keep a cabin cool. I made a sunshade out of Sunbrella and attached it with velcro to the handrails above the salon windows and angled them out to the bow rails. Having them off the window itself helped keep the windows cooler. I made the one reversible so it would fit on either side and would deploy it on the sunny side of the boat. With it only on one side it left the other side accessible for going to the bow.
 
I'm in the "go marine self contained" camp. We have a smaller Cruisair system in the forward part of the flybridge and it is ducted directly down into the salon. The return is in the middle and the output is split on either side. Works very well with that configuration and the ducting is very simple. We have a second smaller unit under the salon floor that feeds only the stateroom.
Only downside to the one in the flybridge is the extra weight up there.
 

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