Minisplit condensor unit in marine environment

[DavidM]

We sometimes debate the wisdom of using a minisplit system for heating and air conditioning on our boats, or an RV unit. I have noted that if you do so you have to consider it a throw away item because the salt water environment will ultimately corrode it out.

So here is a picture of a minisplit condenser. It is located 100 or more yards from the shore and at about a 100' elevation in a hotel in Bermuda. It is not exposed directly to salt spray, just high humidity. I can't be sure of the age, but it is hooked up to a Samsung Smart Inverter interior unit that looks pristine. I think they have only made these for the last 5 years or so.

They are efficient and relatively cheap (well compared to a raw water cooled marine unit) but you need to be prepared to replace at least the outdoor unit every 5 or so years. If they made the housing out of SS it would last longer, but I suspect the market for such will be small. And FWIW the one pictured is still working.

David

 

[psneeld]

Cover it or replace the outer shell with stainless or fiberglass (not all that much money...and well the insides might still rust...but there are bits and pieces of steel on my boat (many engine parts just as exposed as boxes on a boat deck, etc)...and we live with taking care of and/or replacing those rusty items.


But to be fair...I just dropped 4 grand on 3 new marine, water cooled air conditioners...in the long run till these mini-splits are designed for boats of my size...I'll stick with what works for the size...


If I had a LARGE 42 footer like a KK42 or bigger and better...I might figure out how to make mini-splits work.

 

[Ski in NC]

Dave- Here on the coast the sea breeze brings in salt mist. Really a problem right on the beach front and maybe 1000yds inland. Friends with beach houses have to replace condensing units like every five years. Salt mist just eats them up like that Bermuda unit. Park your car overnight and there is salt scum on the windshield.

I'm about 1.5mile from the beach strand as the crow flies, and get a little bit of salt mist. Mainly when there is a strong onshore breeze. Condensing units live nearly a full life here.

I'm about to build a new house and when I get to the mechanical stage I may go with multiple minisplits vs one or two big units with complicated zone control. Just not at that point yet.

For boats, Mermaid package units have served me well. It would have to be a big boat for minisplits to be practical.

KEEP COOL!!!

Eric

 

[DavidM]

Eric:


Since you are building a new house and are fairly geeky like me, get a copy of Bill Maclay's book- The New Net Zero: Leading Edge Construction..... It is a primer on design and construction techniques to achieve Net Zero, a zero purchased energy concept.


Even if you don't go that far, the design concepts can be applied to any new construction and will usually pay for themselves. Bill is not a HVAC expert, but he does recommend mini-split, inverter technology heat pumps. These can achieve a SEER of almost 20 and produce useable heat down to 0 deg F.


David

 

[Ski in NC]

Dave- I'm going to go "close" to net zero, but not going overboard in that direction. The house may go on the weekly rental market with a boat slip, so it has to be user friendly, fairly conventional and idiot proof. Most of the strange stuff will be for heating, and I will be in it then and can be geeky and fiddle. I don't like being cold. I am happy with minimal AC, just knock the humidity down and cool it a bit and I'm happy.

I could see minisplits working for a rental as the various rooms can have individual control. If someone wants to freeze when they sleep, they don't have to freeze the whole house.

Right now I'm waiting on permits. Got my CAMA one and that was the big IF. Done. Massive relief there. Now plans are getting reviewed and I'm sitting on my butt waiting for emails, etc. Not used to waiting for other people to do stupid stuff. Aggravating. I want to get on with it!!! Needed a change to dwgs. No big deal. Oh, wait, draftsman backed up and a simple change took over a frigging MONTH!!! Arrgh.

Building boats is friggin EASY!!! No permits!!!

 

[FF]

Went all up and down the coast from Greece to Turkey last summer.

They are as common as dirt mounted outside attached to the stern rail of boats from 35 ft to 100+ ft.

The hassle I see is the size that will run on USA 120v is limited , 15,000btu or so .

I would hate to have to bypass the older nicely located marinas that do not have 240 .
Two 120v units might be required for 30,000 btu + of cooling if the boat is large.

I expect the better boat assemblers will create mounting areas for these units as they become common in the USA.

With high priced juice in Euroland they are decades old.


Their cooling is better , esp if you are creating or paying for the juice., they will run slower with less load.

Best tho is their ability to heat at 300% to 500% better than a toaster wire , even in Norway at -30F.

 

[Ski in NC]

Unless a larger boat, I think both the interior console and the outside condensing unit would be hard to fit into the boat, and aesthetics not soo good either. Big boats a lesser issue.

Those interior consoles are something Americans are not quite used to, yet. Boat or house.

 

[harbor950]

aesthetics not soo good either.
Those interior consoles are something Americans are not quite used to, yet. Boat or house.

They are coming along. Daikin offers several models including these: