How do you keep your cabin cool?

DianneB

Petty Officer 1st Class
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Feb 8, 2010
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303
Re: How do you keep your cabin cool?

5000 Watts at 12 volts???? That's 417 Amperes! That's a quick way to kill a battery!
 

roncoop75

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Jun 23, 2010
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Re: How do you keep your cabin cool?

5000 Watts at 12 volts???? That's 417 Amperes! That's a quick way to kill a battery!

Ya, at max load. The real problem with them is that they aren't very efficient. You already have limits to how much current you can supply on a boat, burning up 40% of that to generate heat in the inverter isn't a good idea. You'd be better served spending the money on things that run on 12v.
 

Cofe

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Re: How do you keep your cabin cool?

5000 Watts at 12 volts???? That's 417 Amperes! That's a quick way to kill a battery!

Small window air conditioners use around 500 watts. If two batteries hooked parallel powering a 1000 watt inverter. Should work:confused:
 

sasto

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Jun 1, 2010
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Re: How do you keep your cabin cool?

The bilge blower workes good for me on an old weekender. I plumbed it up with the inlet on the hullside and the exhaust to an overhead A/C duct. I'm used to 90 degree weather and it works well for me. The boat with A/C is set at 76 which will freeze me out, maybe I'm not a good example.
 

rwidman

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Re: How do you keep your cabin cool?

Was looking at Harbor Freight Tools and wondering...........

They have 12 volt power inverters up to 5000 watt continuous 110v output.
Would a small window air conditioner from wally world work with a inverter?

No. Not unless you lined the bilge of your boat with batteries. Chances are, a single battery would not be able to provide the power to even start the air conditioner. If it did, it would work for a few minutes before it needed charging.

There are all sorts of calculations that you could do, but consider this:

If it were practical to air condition a boat with battery power, manufacturers would do it. Shop around - you won't find boats with 12 volt DC air conditioning. I think there is one aftermarket 12 volt marine airconditioner, but still, you will need four hundred pounds of batteries to get a few hour's cooling from it.
 

rwidman

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Re: How do you keep your cabin cool?

A marine airconditioner is more efficient than a houshold window airconditioner because it uses sea water rather than ambient air for removing heat. The sea water is typically cooler than the surrounding air.
 

rwidman

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Re: How do you keep your cabin cool?

Small window air conditioners use around 500 watts. If two batteries hooked parallel powering a 1000 watt inverter. Should work:confused:

That's roughly 50 amps from the batteries not counting the 10%-20% inefficiency of the inverter. The inverter will get hot and contribute to the heat load.

Since you should not discharge a deep cycle battery more than 50%, you'll get, at best, two hours of cooling before you have to recharge the batteries. It will take a very long time for your engine's alternator to recharge the batteries from this level of discharge.

My guess is, more like one hour of cooling from 130 lb of batteries.
 

JoLin

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Re: How do you keep your cabin cool?

That's roughly 50 amps from the batteries not counting the 10%-20% inefficiency of the inverter. The inverter will get hot and contribute to the heat load.

Since you should not discharge a deep cycle battery more than 50%, you'll get, at best, two hours of cooling before you have to recharge the batteries. It will take a very long time for your engine's alternator to recharge the batteries from this level of discharge.

My guess is, more like one hour of cooling from 130 lb of batteries.

psst... 500 watts = 4.2 amps@12V, not 50. (amps=watts/volts)
 

skargo

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Re: How do you keep your cabin cool?

We just have a small cuddy cabin on our 21' boat. When anchored we are typically facing into the breeze, and opening the hatch catches it. It's actually pretty cool down there most of the time, but we don't spend a ton of time down there.

That swamp cooler in a cooler thing looks neat, I wonder if block ice or dry ice would work better than cubed?
 

tyler3135

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Aug 19, 2010
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Re: How do you keep your cabin cool?

I have AC in my boat but only at the dock.

Away from the dock, I have a hatch, windows, portholes, and an oscillating fan. These (except the fan) all need to be closed underway or water will get into the cabin.

When anchored, the boat will point into the wind unless the current turns it. The breeze is usually enough to make it comfortable. If it's hot, we don't wear a lot of clothes.

When the party starts, I wanna be on your boat ;);)
 

rwidman

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Re: How do you keep your cabin cool?

We just have a small cuddy cabin on our 21' boat. When anchored we are typically facing into the breeze, and opening the hatch catches it. It's actually pretty cool down there most of the time, but we don't spend a ton of time down there.

That swamp cooler in a cooler thing looks neat, I wonder if block ice or dry ice would work better than cubed?

Dry ice is frozen carbon dioxide and I don't think you want that in your cabin. It's not carbon monoxide which will kill you, but carbon dioxide can displace the oxygen in the air with the same effect.
 

skargo

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Re: How do you keep your cabin cool?

Dry ice is frozen carbon dioxide and I don't think you want that in your cabin. It's not carbon monoxide which will kill you, but carbon dioxide can displace the oxygen in the air with the same effect.

hehehe, thanks! :redface:

Could dry ice be sealed up somehow as to not release the carbon dioxide?
 

cwhite6

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May 7, 2006
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Re: How do you keep your cabin cool?

My father in law worked for Willcool for a few years. It is an A/C unit based of a water cooler. It has a unit that replaces the top of the cooler with a fan and controls on it. He still has two of them at his house. The military was buying them to use in field hospitals and such. It could run off of 12V DC. It would stay cool for a long time as the Igloo coolers are pretty well insulated.
 

LadyAnya

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Aug 15, 2010
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Re: How do you keep your cabin cool?

I think I just may put some fans and be done with it.
 

rwidman

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Re: How do you keep your cabin cool?

hehehe, thanks! :redface:

Could dry ice be sealed up somehow as to not release the carbon dioxide?

It would be like a balloon. Bigger and bigger until .................... pop!

I suppose you could vent it outside of the boat.
 

25thmustang

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Mar 20, 2008
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Re: How do you keep your cabin cool?

I keep my 4 portholes, 2 side windows, 3 hatches and the cabin door open. When overnighting, we have been at the dock only and use a small fan to keep us cool.

New England isn't as hot and muggy as other areas, so it hasn't been an issue yet.
 

Todd157k

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Jul 12, 2010
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Re: How do you keep your cabin cool?

If you want to be a little tricky, get a small electric water pump (like a bilge pump) and a small aluminum radiator with a 8" (auto) fan attached to it. Feed the water from/to the lake through a couple garden hoses.
Your own little cooler that would probably run on one battery all day.
 

Fireman431

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Sep 17, 2007
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Re: How do you keep your cabin cool?

How do I keep it cool? 28,000 BTU's of chilly air and lots of mommy/daddy drinks! :cool:
 
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