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Yet Another A/C Solution for the Mac?
Posted: Mon Jul 17, 2006 11:30 pm
by kmclemore
OK, so I know it sounds crazy, but check out
this air conditioner unit! (slightly different version seen
here) Yeah, I know it's made for dogs, but take a look at the size of that thing - it's tiny! Plus, it not only will cool, but also puts out
heat, too!
It only uses 285 watts on cool and 585 watts on heat (well within the capacity of a Honda EU1000i, and less than any other A/C I've ever seen), and with 2,000BTU's it will cool a 10'x10'x8' space - that's just a bit smaller than a Mac's interior, but then half of the Mac is under water, so perhaps that makes it a little easier to cool?
As far as installation goes, no special adapters are required, it's made to sit outside in the weather on nice rubber feet, and only weighs 39lbs.. Just hook up some ducts and you're good to go. Heck, I'll bet it might even fit under the Mac's transom seat.

What do you think? Is this cool, or what? (sorry for the pun)
Posted: Tue Jul 18, 2006 1:03 am
by David Mellon
Actually I think this may work for me. I would only use AC onboard at night. So, a very small unit should cool the boat enough for sleeping. It seems to me that I could use standard inspection ports for the hoses which could house solar vents when the AC isn't in use. It appears to be small enough to store onboard for summer overnights. Also, the ports could be placed over my bunk. The crew can stew while I slumber in comfort

Posted: Tue Jul 18, 2006 1:33 am
by RobertKing
One on Ebay right now for $419, I would prefer the 5000 BTU main hatch way, plus they are $79 at WallMart. Reserve power, kinda like having an A/C hotrod.
Posted: Tue Jul 18, 2006 1:55 am
by James V
kmclemore - perty cool. With this I would not to have to buy the 2000W generator. A 1000W would do. This would more than offset the cost differance in the 5000 btu unit and is small enough that I can get out of the hatch without removing the A/C. Small emough to store inside with all of the other SMALL stuff. The next thing that I need to work out is where to put all of the SMALL stuff.
Posted: Tue Jul 18, 2006 4:53 am
by Rich Smith
Brilliant! I think you're on to something! Let us know if you try this...
Cheers,
Rich.
Posted: Tue Jul 18, 2006 7:53 am
by Chip Hindes
Tiny in more ways than one. We found a 5000 BTU unit to be marginal for the X on several hot nights in North Carolina a few weeks ago. I'm afraid 2000BTU would have been seriously undersized.
The boat being half underwater does not ease the cooling loads if, as frequently occurs in the tropics, the water temp is 80F or higher.
Posted: Tue Jul 18, 2006 8:30 am
by DLT
My 5000 BTU unit does the job fine, but it is certainly NOT more than double the size needed...
Keep in mind that the boat is not insulated at all, not shaded at all (on the water, and not at all air tight. So, cooling it is VERY inefficient, and you really need more BTUs that the 'space' might otherwise require...
Now, with that said, those of you who typically have only a crew of two and only use the aft OR bow berth, might be able to curtain that berth off and this unit may very well be able to cool such a reduced area...
For me, I'm going to stick with my 5000 BTU unit in a door in the companion way. My eu1000i will run it, just not in smart throttle mode.
Posted: Tue Jul 18, 2006 10:45 am
by kmclemore
Well, I guess my objective wouldn't be to make the cabin like home, but just to take the 'edge' off, and de-humidify things a bit.
Posted: Tue Jul 18, 2006 11:24 am
by Chip Hindes
Well, I guess my objective wouldn't be to make the cabin like home, but just to take the 'edge' off, and de-humidify things a bit.
Heck, Kevin, you can do that with a couple 12V fans.
Seriously, it's a good point that you can arrive at approximately equal bucks compared to a cheap window AC and an EU2000 by going with this one and an EU1000, though.
If $$ were no object, I'd definitely spring for the Mermaid unit. Since it isn't ($$ no object, I mean) if I'm going to go for the expense, weight and bother of A/C to begin with, I want one that does more than just take the edge off. And for the equal $$, I'd just as soon go for the extra capacity on the generator; makes it more versatile for other stuff.
Does give me the idea to try an alternate installation though. I was planning on a more "conventional" version wth the A/C sitting on the cockpit floor and blowing through an opening in a modified hatchboard. Now I'm thinkng it should not be too tough to do a ductwork adapter on the window A/C.
I'm questioning what to do about the front control panel though; pretty sure you don't want that to be out in the rain.
Posted: Tue Jul 18, 2006 1:27 pm
by DLT
Chip Hindes wrote:I'm questioning what to do about the front control panel though; pretty sure you don't want that to be out in the rain.
Yeah, the controls on mine are certainly not waterproof. But, more than that, you may find you want access to them while inside...
The tricky thing about the duct work, is that you have to have two ducts, and you'll want them insulated. You need two, or you'll just be trying to cool 90-100deg air, which won't work very well. You'll want them insulated, or you'll loose 'cold' to the ducts themselves...
An EU1000i is really all you NEED to run a ~5000BTU unit... Granted, the extra capacity for a EU2000i might be nice, but I was also considering the space. You can actually walk past a EU1000i sitting on the cockpit sole...
Reduce
Posted: Tue Jul 18, 2006 3:52 pm
by Night Sailor
The trick we use in winter to keep the sleeping area warm with a small amount of heat is to close off all but the sleeping area with a curtain. Do the same to keep a small A/C unit useful by cooling only the sleeping area after dark.
If you have a large crew so closing off a portion of the boat is not a solution, then remember that in additon to ambient temps, each person's body heat is equivalent to that of a 100 watt bulb, so the more people in a closed space, the more cooling capacity you'll need.
Posted: Tue Jul 18, 2006 8:24 pm
by James V
You need to also consider how much bad air will be in the cabin after it is closed up all night. Per that I understand you need 3 cubic feet of fresh air per hour per person. With all hatches closed you do not have that.
With the small unit you could just take the outside air and bring it in. This would handle the problem.
Posted: Wed Jul 19, 2006 6:59 pm
by Chip Hindes
The tricky thing about the duct work, is that you have to have two ducts, and you'll want them insulated.
Of course you need two ducts; that's not even a question. But if you keep the ducts relatively short you aren't going to lose a lot of cool through the duct walls; insulation will reduce the flexibility of the ducts as well. The ducts of the mini unit don't look like they're insulated either.
With the small unit you could just take the outside air and bring it in.
Every AC unit I've ever seen has the capability to recirculate the inside air, or bring in outside air.
Besides, even a well sealed up Mac is going to leak quite a lot of outside air.
Posted: Wed Jul 19, 2006 7:14 pm
by DLT
Every window unit I've ever seen will allow you to recirculate inside air, but none have had any provision to bring in outside air.
There has been more than one person who has considered a dock mounted AC unit with only one duct... But, yes it was a statement, not a question...
Posted: Thu Jul 20, 2006 2:19 pm
by Scott
As we frequentlyovernight in our slipI posted the dock box A/C thread, and we also overnight in coves so yes I posted the lakewater to heat exchanger thread ( Im the moron)
A more reasonable question would be in order so here goes. For those that have actually run a generator and/ or A/C on their boat not just theorized, how much noise transfer do you get into the cabin.
Seems as though regardless of how quiet your generator and A/C is you would have vibrations and resonance would make the hull act like a drum or very large speaker????
Kinda like the two good old boys racing along in the bass boat at 55 mph, one screams over the roar of the engine "Isnt nature great?" "what?" "isnt nature great?" "What" "NEVER MIND"