Air Conditioning for an A-25

[NickScheuer]

Wife and I had a brainstorm last evening concerning low-cost AC for our A-25, the DuNORD. Most of you (USA & Canada anyway) have probably seen those ads running currently on the internet for small battery-powered AC units about the size of a "toaster" listing for $89.They claim to cool a small room in minutes. Well, says dear wife, "the boat is smaller than a "small room, right?" Amazon lists them for only $69, with delivery TODAY! We'll report how it works out, eh?

[DesertAlbin736]

Battery powered? Are we talking running off 12V lighter plug or a rechargeable Li-Ion unit? Think for a minute, "pumping heat", which in essence is what an air conditioner does, lowering indoor temperatures by removing "heat" from inside and pumping (pushing it uphill as it were) it outside is thermodynamically an energy intensive thing to do. There's no cheating laws of physics. The little battery powered "personal air cooler" units are actually evaporative coolers. Being a desert rat I'm very familiar with these things we call "swamp coolers" meant to work in dry climates with dew points below 55*. What it is is a fan (low amp draw, hence able to be battery powered) blowing air through water soaked pads or grids, which if the air is dry enough will evaporate the water and absorb heat in the process. They work great when humidity is like 10% to 20% desert air and dew points are in the 40s. They can take in air at 100* and put out air at 67*. The catch is it adds humidity to that cooled air in the process. So if you're in a marine environment where the humidity is already above say 60% to 80% and dew points well over 55* they're not going to do much. That's why in Arizona where "swamp coolers" used to be ubiquitous in times past home builders stopped using them in new homes over 30 years ago. At large scale sizes big enough to cool a house they are maintenance intensive because the pads had to be replaced every year and whatever salt & minerals (AZ has lots of hard water) are in the water get concentrated & left behind causing rust and scale issues on the old painted steel units. Plus, during Arizona's "monsoon" season in late July through September when prevailing weather patterns shift from west to south and draws in moisture from the Sea of Cortez and raise humidity to the upper 30s percent and dew points rise to over 55 or 60 degrees they're pretty much useless, hence the slang term "swamp cooler".

So in this case caveat emptor.

[Ben423]

NIce explanation, DA.

[Bob Noodat]

Looked on Amaz-onlymakinjeffAmazinlyricher.com. Yep, those are swamp coolers and by any other name would make your A25 smell as musty.

A little pricier, but if a couple of 12v fans won't do the job, then this might:

https://www.marinaire.com/Marine-air-co ... sba6k2.htm

Draws only 6 amps max @120v.... run it off a battery and inverter?

[NickScheuer]

Yep, "swamp cooler". But the more serious problem is that "battery powered" means one plugs it into a portable computer with a USB cord. There is no way I'm burning laptop power to run a friggin' fan. Already have an Amazon return code to ship it back tomorrow.

[Scudrunner]

Battery powered? Are we talking running off 12V lighter plug or a rechargeable Li-Ion unit? Think for a minute, "pumping heat", which in essence is what an air conditioner does, lowering indoor temperatures by removing "heat" from inside and pumping (pushing it uphill as it were) it outside is thermodynamically an energy intensive thing to do. There's no cheating laws of physics. The little battery powered "personal air cooler" units are actually evaporative coolers. Being a desert rat I'm very familiar with these things we call "swamp coolers" meant to work in dry climates with dew points below 55*. What it is is a fan (low amp draw, hence able to be battery powered) blowing air through water soaked pads or grids, which if the air is dry enough will evaporate the water and absorb heat in the process. They work great when humidity is like 10% to 20% desert air and dew points are in the 40s. They can take in air at 100* and put out air at 67*. The catch is it adds humidity to that cooled air in the process. So if you're in a marine environment where the humidity is already above say 60% to 80% and dew points well over 55* they're not going to do much. That's why in Arizona where "swamp coolers" used to be ubiquitous in times past home builders stopped using them in new homes over 30 years ago. At large scale sizes big enough to cool a house they are maintenance intensive because the pads had to be replaced every year and whatever salt & minerals (AZ has lots of hard water) are in the water get concentrated & left behind causing rust and scale issues on the old painted steel units. Plus, during Arizona's "monsoon" season in late July through September when prevailing weather patterns shift from west to south and draws in moisture from the Sea of Cortez and raise humidity to the upper 30s percent and dew points rise to over 55 or 60 degrees they're pretty much useless, hence the slang term "swamp cooler".

So in this case caveat emptor.

I agree, I too lived in Arizona. Evaporated coolers are great with low humidity. I highly doubt they would work in a marine environment.

[Scudrunner]

I too have thought about AC on the Albin. Summer nights in the South can be brutal on sleep... I know from years of having a sailboat. What I think might work is an ultra quite Honda inverter, which are incredible, and a portable AC when on the hook. Here is what I think would work. https://www.amazon.com/dp/B01DLPUWL2/re ... ERJF90PZQQ

[Bob Noodat]

I too have thought about AC on the Albin. Summer nights in the South can be brutal on sleep... I know from years of having a sailboat. What I think might work is an ultra quite Honda inverter, which are incredible, and a portable AC when on the hook. Here is what I think would work. https://www.amazon.com/dp/B01DLPUWL2/re ... ERJF90PZQQ

Before buying this B&D portable room ac, I'd read this article, which rates it worst of a bunch:
https://www.techgearlab.com/reviews/ele ... -bpact08wt

We used to have this type (but different make) of air conditioner in our previous house, in Oregon. It certainly made summer sleeping much more pleasant, BUT....

They have a 6" diameter or greater 6' long hose to vent the hot air, and it must vent outside, obviously. You could adapt a drier-type vent, but it would be a hassle in a boat. The hose also gets hot, and it takes up space. These units are quite bulky, and take up even more space. This would soon get old in a small boat cabin. Where does it go when you don't need it, or want to cook or dress?

Our unit weighed over 50lbs. It would roll around on casters. On a boat, do you want it rolling around at night, or do you remove the wheels and have a 50lb deadweight to lug around? Hmm.

They are all tall and would be very tippy in a boat. You'd have to strap or bolt it down. How and where?

They are all very noisy.

Another hassle is the water that is distilled from the air while cooling. Our ac had a gallon container that I would need to get up and empty twice a night. Oregon is much drier than the east coast or midwest, and a boat is humider still. You would have a lot of water to get rid of, although you could theoretically pump it to your fw tank, since it is quite pure.

Finally, these units use a lot of power, at least in boat terms. If you are suggesting buying a Honda 1000eu inverter and a portable ac, the overall cost is identical to buying one of the dedicated compact marine units that I list above.

[Scudrunner]

I too have thought about AC on the Albin. Summer nights in the South can be brutal on sleep... I know from years of having a sailboat. What I think might work is an ultra quite Honda inverter, which are incredible, and a portable AC when on the hook. Here is what I think would work. https://www.amazon.com/dp/B01DLPUWL2/re ... ERJF90PZQQ

Before buying this B&D portable room ac, I'd read this article, which rates it worst of a bunch:
https://www.techgearlab.com/reviews/ele ... -bpact08wt

We used to have this type (but different make) of air conditioner in our previous house, in Oregon. It certainly made summer sleeping much more pleasant, BUT....

They have a 6" diameter or greater 6' long hose to vent the hot air, and it must vent outside, obviously. You could adapt a drier-type vent, but it would be a hassle in a boat. The hose also gets hot, and it takes up space. These units are quite bulky, and take up even more space. This would soon get old in a small boat cabin. Where does it go when you don't need it, or want to cook or dress?

Our unit weighed over 50lbs. It would roll around on casters. On a boat, do you want it rolling around at night, or do you remove the wheels and have a 50lb deadweight to lug around? Hmm.

They are all tall and would be very tippy in a boat. You'd have to strap or bolt it down. How and where?

They are all very noisy.

Another hassle is the water that is distilled from the air while cooling. Our ac had a gallon container that I would need to get up and empty twice a night. Oregon is much drier than the east coast or midwest, and a boat is humider still. You would have a lot of water to get rid of, although you could theoretically pump it to your fw tank, since it is quite pure.

Finally, these units use a lot of power, at least in boat terms. If you are suggesting buying a Honda 1000eu inverter and a portable ac, the overall cost is identical to buying one of the dedicated compact marine units that I list above.

I just used as a reference and one based on Amazon reviews.

[Burton]

We are pretty much big babies up here in Maine when it comes to heat and humidity. We do get a few weeks when being in a boat is pretty unbearable. We had a West Wight Potter 15, and that is some tight quarters for sleeping! So our A25 feels like a luxury yacht compared to that! We just got two 12 V fans, the ones recommended by practical sailor, and I’ve got plans to mount them before the heat hits, pointing at both sides of the V berth. With two house batteries, their amperage draw is low enough to not be a problem. Perhaps in the hotter climates one could do this, and then the fans will be evaporative coolers for the sweat running off of bodies? I had a friend with a big beard and he said that his beard was an evaporative cooler in the summer time.... so maybe instead of people getting these waxing jobs to get their hair pulled off, us boaters without AC could add some hair planting and a water spray bottle and be all set! .

[tribologist]

Did you guys see the install of the 10k btu Dometic unit we put in to Driftless? It fit perfectly in the cubby made for the diesel heater.

[tribologist]

Did you guys see the install of the 10k btu Dometic unit we put in to Driftless? It fit perfectly in the cubby made for the diesel heater.

https://www.defender.com/product3.jsp?n ... id=1848284

[tribologist]

Did you guys see the install of the 10k btu Dometic unit we put in to Driftless? It fit perfectly in the cubby made for the diesel heater.

https://www.defender.com/product3.jsp?n ... id=1848284
It run fine off a Honda EU2200i. The 6000 btu unit might be a little bit easier to fit in and it probably would do the job too but the 10k unit is not to big.