Evaporative Cooler Aboard in the California Delta...???

The friendliest place on the web for anyone who enjoys boating.
If you have answers, please help by responding to the unanswered posts.

Astral Blue

Veteran Member
Joined
Apr 8, 2012
Messages
71
Location
Sacramento, CA
Vessel Name
Astral Blue
Vessel Make
Bayliner Victoria 2750 Command Bridge
We have had several hot (105 degree plus) weekends this summer and I'm anticipating more to come. Fortunately, the unbearable segment of the day is in the late afternoon, and lasts about 2 hours. During several of these weekends, we have been anchored out during this heat and have not had access to shore power.

Our boat does not have a generator and there are no plans to purchase one. The evaporative coolers I've seen use at little as 20 watts AC and my capacity with my house batteries and inverter could easily accommodate two hours of its use.

I'm wondering if anyone here has used an evaporative cooler on their boat; and if so, what has your experience entailed? My goal is to bring the temperature down about 20 degrees, which is what most evaporative coolers I have considered claim to do.

The heat in the California Delta is relatively dry. While we are on a body of water, the relative humidity in the summer rarely exceeds 40 percent; and even 40 percent is rare.

What are your thoughts?
 
I would think it should work in your conditions. You essentially have an endless supply of fresh water and that low humidity will let a cooler work quite well. Heck, you could make your own with a DC pump and a high CFM fan and stay with DC power. Only draw back I can think of is that you will need a fairly large surface area for the effect to work well.

Marty.....................
 
I live in NM, very dry climate. We use these type of coolers. On our hottest and driest days they are very effective. We are currently in out Monsoon season, average humidity levels around 50% and higher, coolers are ineffective. Keep in mind that during our rains, we have lower temps in general.

The dryer your climate, the more effective theevaporative coolers are. You also need proper air flow/ventilation to push the warmer air out.
 
We live near the Delta and though our house is equipped with air conditioning we rarely use it. The evaporative cooler is more than sufficient to cool the house, and it's a relatively small unit too. I hooked up my Kill-a-watt meter to it and it averages 4 cents per hour of operation.

I agree with the above posters recommendation that a DC only unit can make a huge difference on your boat and am considering building one for ours.
 
I've never used an evaporative cooler on a boat, but have had a fair amount of experience with it on land.

As you are aware, its all about the relative humidity. Generally they work well below 30% but have very little effect above 40% humidity.

The unit on our house easily reduces the temperature from 38 C (100 F) to 22 C (72 F) with humidity at 25% or less. Here in Adelaide, evap coolers are effective 99% of hot days, but I don't think Sacramento is quite as dry, according to a quick google. I'd suggest looking closely at your local climate records.
 
Evaporative Coolers

The commercially available evap coolers have a reservoir in the bottom that would spill out in a boat that moved at all. I would think that a relatively small dc water pump would work well for the water to be supplied to the evaporative elements but you would have to plumb it from either a closed reservoir or the river itself. Evaporative coolers rely on a pretty hefty volume of air flowing over the elements so a pretty large dc fan would be needed as well, but it should do the trick. I've seen pretty hefty greenhouse fans run off of pretty small solar panels, so I'm sure there are good fans available. The house sized coolers have three evap panels, making them somewhat bulky, but for a boat you may be able to fabricate a cooler that would run off of one good sized panel, like the Port-a-Cools at NAPA.
One thing I have found with the evap colers is that they do well if you stay ahead of the curve, meaning don't let things get baking hot and then turn it on. You have to start a little early and KEEP things cool instead of expecting them to GET cool. I live in Mendocino County and our relative humidity is low, usually 20%, so these coolers work well.
Also, they need a constant source of new water supply, so maybe a supply and return line just thrown over the side with a good filter would work well.
 
Last edited:
Ed, it might work and I have considered it, but for the few hours of the worst heat, we're rarely in the cabin. We're usually out on the decks or in the water at that time. I have concentrated on shading the cockpit and misters on the raw water washdown line to supply the water and pressure.

Last summer I installed a temporary cockpit cover that looked extremely redneck but functioned as needed. It was a poor design slapped together at the last minute that was as awkward to install and remove as it was ugly.

img_254313_0_cea79317d8d17bb7bb5797651515371f.jpg


I was inspired by the retractable cockpit shade Moonstruck told me about.

attachment.php


I just returned from the store where I purchased two manually-retractable poles which will support a canvas cover slipped over the ends. This cantilevered cockpit cover will be onboard this month in the delta in prototype form.

I'll also have a small mister bar that I used last summer. It actually works quite well. It puts out a little too much water, but the extra spray cools the cockpit deck nicely. This summer, I'll also try a single free-standing mister jet for personal cool down.

img_254313_2_da1621ed0492d2b76d2d403ec80d4ca9.jpg


Like the evaporative coolers, the misters rely on dry air to evaporate the mist to provide the cooling effect. The cooling effect is noticable with the misters, but that might be somewhat reduced by the higher humidity levels we experience near the water.

This summer, I plan to install my weather station for a better idea of the local temps, winds and humidity levels.
 
Thanks, everyone! I'm going to give it a try! I'll look for a used unit on Craig's List and see if it works. If it gives decent results, I'll invest in a DC powered unit. There are a lot of options on the market for DC powered portable units...and the engergy savings would be considerable since I would be bypassing the inefficiency of the inverter.
 
Check the RV supply stores.
I have seen them for sale there to install on van conversions,
(boogie vans?)
Ted
 
Thanks for the video AusCan :thumb::thumb:

It's amazingly similar to what I had in mind. Nice to see it works.
 
I have no idea what 25% humidity even feels like. Greeting from NC sog-fest swamp conditions, probably 90% RH right now.
 
Thanks for the additional humidity! :rolleyes: Should work well on Lake Powell. (I'm hypersensitive to humidity.) :surrender:

(January is a good time to visit Lake Powell.)

img_260525_0_c80eea5af333a0fbfef8c97a81ca71b4.jpg
 
Last edited:
Inspired by Auscan's post, I have gathered the necessary parts for the 12V Redneck Bucket Swamp Cooler.

img_260529_0_a590834be7c9c2a936fac4c1cf72aeb2.jpg


As you can see, I've used a supersized bucket that will hold about 4-5 gallons at the planned waterline.

I'll give it a go and report back.


I dig the DIY.I can't wait to see this come together.Might as well give it a nice designer paint job. :D
 
In a non A/C environment, I've relied on shade and a breeze or fans to evaporate sweat from my body, nature's cooling system for humans. Got four fans on the boat: one each in the forward cabin and pilothouse, and two in the saloon. ... And I avoid the California Delta in the summer. August is a good time to have the boatyard work on the boat's maintenance.

(Never thought high humidity was good for electrical stuff or a steel boat.)
 
Last edited:
I don't know how y'all do it.
 
I don't know how y'all do it.

I don't know how people can live east of the Colorado Mountains under 5000 feet of elevation.
 
In a non A/C environment, I've relied on shade and a breeze or fans to evaporate sweat from my body, nature's cooling system for humans. Got four fans on the boat: one each in the forward cabin and pilothouse, and two in the saloon.

(Never thought high humidity was good for electrical stuff or a steel boat.)

For natures evaporative cooling to work efficiently,one needs to be in a state of undress. :lol:
 
I don't know how people can live east of the Colorado Mountains under 5000 feet of elevation.


For me that's easy to answer.:D

I'm not looking to derail the thread but just curious what's the average temperature at night during summer time?
 
As a rule here, the nights here turn up to 30 degrees (or more) cooler from daytime temperatures.
 
For natures evaporative cooling to work efficiently,one needs to be in a state of undress. :lol:

I will fix you.....unsee this....... 265lb 67 year old grey haired fat man close to or naked trying to stay cool using a swamp cooler to stay cool. There, take that:lol:
Got ya .......
 
I will fix you.....unsee this....... 265lb 67 year old grey haired fat man close to or naked trying to stay cool using a swamp cooler to stay cool. There, take that:lol:
Got ya .......

I'll be there,I hope,in about 30 years. I'll see it everyday until I'm 68. :lol:
 
I will fix you.....unsee this....... 265lb 67 year old grey haired fat man close to or naked trying to stay cool using a swamp cooler to stay cool. There, take that:lol:

Got ya .......


So you've met FlyWright in person then...

Edit, forgot the :)
 
Oliver, I think the one big difference between our summer and yours is humidity. In the Delta, it's up to 20 degrees warmer than the bay, but the humidity runs about 30-40%. So at 90-95 degrees and 35%, it doesn't take much to make you feel cooler...a breeze (natural or fan), a dip in the fresh water, a FW washdown, a mister or an evap cooler.

Early this month, I was in the delta with those conditions and had a mister spraying in the cockpit. It worked well, cooling me and the decks. As the week went along, the temps cooled into the 80s and no mister was needed, just an occasional fan. Aside from an unplanned swimming event, I didn't feel the need for a swim with the temps in the 80s or lower.

When I travel back home to Chicago to see family or DC, I'm always impressed with the impact that humidity has on my comfort level. It's something I have long taken for granted out west, but my travels east help to remind me of our good fortune.

Oh, did I mention we have few bugs?
stirthepot.gif
 
I will fix you.....unsee this....... 265lb 67 year old grey haired fat man close to or naked trying to stay cool using a swamp cooler to stay cool. There, take that:lol:
Got ya .......

So you've met FlyWright in person then...

Edit, forgot the :)

Hey...I resemble that remark!

Just not that old or big....YET!!
 

Latest posts

Back
Top Bottom