Air conditioning

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alibi 2

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we would like to cool the cabin of our 282...we don't have the room to install a gen and air conditioner...does any one know of a system that isn't a swamp cooler ...that will work off 12 volt?
 
I had a cruiseair 5,000 btu ac/heat installed in my 272. The unit is under the cabin steps Access is under the galley by removing the refer or aft cabin bulkhead.
Also installed 30 amp shorepower. I have a Honda 2000 generator to power it.
Cools & heats great.
 
ahill said:
I had a cruiseair 5,000 btu ac/heat installed in my 272. The unit is under the cabin steps Access is under the galley by removing the refer or aft cabin bulkhead.
Also installed 30 amp shorepower. I have a Honda 2000 generator to power it.
Cools & heats great.
Click to expand...

Which model do you have?
 
alibi 2 said:
...that will work off 12 volt?
Click to expand...

Nothing effective will run off 12vdc, unless you fill the boat with golf cart batteries.

I installed a 6,500-BTU Reverse Cycle A/C from Mermaid Marine Air under the galley furniture, and use a Honda EU2000 to power up when away from shore power.

Brian
 
Where's the Marvair spec sheet on battery capacity vs. compressor duty cycle and SW pump, and run times to come up with your fugures of 8 hrs on three 27s?
 
BobP said:
Where's the Marvair spec sheet on battery capacity vs. compressor duty cycle and SW pump, and run times to come up with your fugures of 8 hrs on three 27s?
Click to expand...

http://69.33.187.224/marvair/pdfs/SM12VDCPDS_31005.pdf

Give that a good read, looking at the capacity in BTUH at various water inlet temps, power draw, etc.

Based on our experience with a 6,500-BTU unit, on the smaller 270, I don't see how this unit will cool down a cabin that is at 98*, without running continuously, if it can do it at all.

Also, note that the power draw is given for the unit, and specifically notes that it does not include the sea water circ pump. No power draw is given for that pump.

I think I'll stick by my initial statement. "Nothing effective will run off 12vdc, unless you fill the boat with golf cart batteries." And I'll "maybe not even then.."

Brian
 
Brian, I'm with you, I'm sure you are directing this at the less informed for their benefit.

But then again the guy could keep the boat's motors running on fast idle for the duration.

I was trying to find the source who quoted this member the 8 hrs on three 27s. It's not the MARVAIR site, I was there.

I do recall seeing a DC unit offered by another manuf of a more common name, and I thought they quoted 3 hrs on three 31s, made more sense to me, though if I was game I would do my own calculations running the compressor and SW pump on 100% duty cycle, but that's just me.

I also wonder will the unit shut down at some voltage level, or just continue to drive the bats bone dry and toast the compressor and SW pump motor in the process.
 
BobP said:
Brian, I'm with you, I'm sure you are directing this at the less informed for their benefit.

I also wonder will the unit shut down at some voltage level, or just continue to drive the bats bone dry and toast the compressor and SW pump motor in the process.
Click to expand...

Just trying to help. Old MechEngr with some AC&R experience. And I did my own installation on the Mermaid...

The spec sheet I linked above gave 9-17VDC as operating range. It also noted a low-voltage shutdown, but didn't give the setpoint. I would hope it isn't nine volts, as that would be pulling a LOT of current and more heat in the motor windings. Aside from really reducing the longevity of the batteries...

Honda EU2000....... just got ours warmed up yesterday, in preparation for TS Hanna. I can keep the refrigerator in the kitchen and the reefer and freezer in the garage going..

Brian
 
Like you said, Honda Gen is way to go on outboards.

Pehaps the DC A/C on big inboards with a real belt driven 60 or 100 amp alternator is better application.
 
http://www.marineair.com/pdfs/L-2425C.pdf

Trust me, this unit works! The 3 batteries can be a chore to locate, but it gets a noisy generator off your deck. Plus, if you swap out the Dometic supplied inverter for one that can be wired to a AC panel, you can run it off shorepower. Many builders are offering this model, as well as the Marvair.

What is my preference? 120V AC air conditioning, fed through a genset or shorepower, no ifs, ands, or buts. But given this owners dilemma, just trying to offer some alternatives. Didn't mean to step on anyone's toes...
 
A/C with limited space

Those that use Honda 2000 gen, where do you put them? Thanks
 
I am not going to dispute whether a 12VDC unit drawing 31amps can run for a specified number of hours on a specified number of batteries of a specified size.

The more basic point is that the unit is rated nominally at 3,500-BTUs, with a good bit less capacity as air and water temps increase.

Based on my own experience with a 6,500-BTU unit in the smaller volume cabin of a 270, I don't think the 3,500-BTU will make this owner happy.

JMHO.
Brian
 
fighterpilot said:
Those that use Honda 2000 gen, where do you put them? Thanks
Click to expand...

I'll check the model & post it for you.

Mine is on the starboard side integral platform. I fabricated a canvas cover that attaches to the gunwale, aft bulkhead and a post set in a rail fitting in the splashwell. I'll take a pic cause it's hard to visualize.
I have several friends that don't bother with the cover but I prefer it in rain.
My 6 gal duration tank sits on the port side. I bungee the tank & gen to the aft bulkhead out of caution. Even though both sit on non-skid foam the gen will walk when the deck is wet.
 
Re: A/C with limited space

fighterpilot said:
Those that use Honda 2000 gen, where do you put them? Thanks
Click to expand...

Open the tuna door. Put the EU2000 on the stbd side of the platform. Exhaust facing aft, connections forward. Short heavy-duty extension cord to a one-piece Marinco adapter, directly in to the shore power inlet box. Tie generator to the handrail on the angled section of the eurotransom. Duration tank on the aft seat, about same level as the generator.

Have also set it up forward, in the walk-around area directly aft of the anchor locker. Longer extension cord to reach the shore power inlet.

CO detector mounted on overhead in the cabin.
 
I run a Dometic ac unit on my 272 mounted under the galley with a Honda 2000 EU.
Works great, I'm in south FL.
Get a Duration remote tank and you can run for days. Duration.com
 
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