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Re: 12 volt cooler or refrigerator

Posted: Wed Jan 17, 2018 6:40 pm
by Sumner
1st Sail wrote:Can you leave an Engle or equivalent in the boat while traveling on the trailer without damaging the components? I don't load the boat when traveling but that is one item I prefer not to lift on and off.
Ours never comes out unless like now when we bring it to FL as a backup just in case we have a problem with the one on the boat there (hasn't happened so far). Truckers use these all the time,

Sumner

============================
1300 miles to the Bahamas and back -- 2015

The MacGregor 26-S

The Endeavour 37

Trips to Utah, Wyoming, Idaho, Canada, Florida

Mac-Venture Links

Re: 12 volt cooler or refrigerator

Posted: Wed Jan 17, 2018 9:17 pm
by Russ
BOAT wrote:
Trust me, I have eaten a LOT of meals over my life grilled on a boat!

The big difference is that "Back in the Old Days" we did not have those fancy chrome West marine BBQ jobs with propane bottles and stuff like like that picture above you new fangled modern people use today - nope!

Back in the old days there Were NO BBQ units for boats - but that did not stop my dad - he built one out of black sheet metal and that sucker ran on CHARCOAL and WOOD CHIPS!!
If you really want a treat try a huge boiling pot shrimp boil on the beach in Mexico.
Yup. Our first grill was charcoal. I'm sure it alarmed nearby boaters when starting it with all the smoke and such. You are right. THAT was the best.

We had a place called "Lobster Bake in a Bucket". They'd put all the goodies (Lobster, clams, corn on the cob, potatoes, etc.) in a big metal bucket. Cook that sucker on the beach and you are eating. Sounds like your experience.

BTW...grilled food is the easiest to cook. Toss some burgers on there and take em off and eat. Simple and yummy.

--Russ

Re: 12 volt cooler or refrigerator

Posted: Wed Jan 17, 2018 9:19 pm
by Russ
Sumner wrote:
1st Sail wrote:Can you leave an Engle or equivalent in the boat while traveling on the trailer without damaging the components? I don't load the boat when traveling but that is one item I prefer not to lift on and off.
Ours never comes out unless like now when we bring it to FL as a backup just in case we have a problem with the one on the boat there (hasn't happened so far). Truckers use these all the time,

Sumner

Same here. The thing is pretty unruly to lift in and out of the boat, so ours just sits there. I put in next to the sliding galley. It's been working well there.

--Russ

Re: 12 volt cooler or refrigerator

Posted: Thu Jan 18, 2018 1:53 am
by Neo
Sorry only just seen this thread.... It's funny but a cooler is something I've been considering lately.
One thing I do not like about any stand alone fridge (on an :macm: at least) is that it gets exposed to the sun in most places (that are easily accessible) in the cabin ..... This cannot be helping the fridge stay cool!!
So I've been considering making a cheap cooler out of Thick Thermal Polystyrene, CoroPlastic, thermoelectric unit and enclose that box inside one of the lockers (not sure which one yet) where it stays cool because of the cool fiberglass/water below.
I have no idea how good, effective or efficient it will be but I think it's worth a try.

Another idea I've had is to use a heat exchanger setup to continuously pump ballast/cooling water over the heat sink. I'm have no doubt this will rot away (soon) but should easy to replace with another on a regular basis.

Anyway just voicing some idea :)

Re: 12 volt cooler or refrigerator

Posted: Thu Jan 18, 2018 5:44 am
by Sumner
Neo wrote:...One thing I do not like about any stand alone fridge (on an :macm: at least) is that it gets exposed to the sun in most places (that are easily accessible) in the cabin ..... This cannot be helping the fridge stay cool!!...
If the sun is hitting ours we just fold up a towel and put it on the top of the fridge. They also make insulated blankets for that.

Image
http://purplesagetradingpost.com/sumner ... age-2.html

I tried to get as much insulation at the bottom of the one I made for the Endeavour since that is the area that has the biggest heat differential. Cold air drops leaving the coldest air at the bottom of the box.

Image
http://purplesagetradingpost.com/sumner ... age-1.html

I have 7" and 9" at the bottom of the box.

Image
http://purplesagetradingpost.com/sumner ... age-9.html

The Endeavour fridge doesn't go down to the hull and the compressor is under it. That area is now well ventilated.
Neo wrote:....So I've been considering making a cheap cooler out of Thick Thermal Polystyrene, CoroPlastic, thermoelectric unit and enclose that box inside one of the lockers (not sure which one yet) where it stays cool because of the cool fiberglass/water below.
I have no idea how good, effective or efficient it will be but I think it's worth a try....
I'd encourage you to forget the thermoelectric and use a compressor type. The compressor can be mounted in an area that normally can't be used for much. If I was to do it again that is what I would do as then I could add more insulation to the unit. Walt on the other Mac board did this when he made a fridge for his 26S, You could buy an EdgeStar for less but you would have about as much in it as one of the higher priced fridges and it could be larger and more efficient than they or the EdgeStar are,

Sumner

============================
1300 miles to the Bahamas and back -- 2015

The MacGregor 26-S

The Endeavour 37

Trips to Utah, Wyoming, Idaho, Canada, Florida

Mac-Venture Links

Re: 12 volt cooler or refrigerator

Posted: Thu Jan 18, 2018 6:31 am
by Russ
Neo, I don't think there is any way to make a thermoelectric work. They are a novelty.

Your idea is a good one to make a compartment insulated.

Venting a compressor is important. My last boat had the compressor in a side compartment and it got HOT. I'm sure it lowered efficiency.


--Russ

Re: 12 volt cooler or refrigerator

Posted: Thu Jan 18, 2018 7:04 am
by Tomfoolery
RussMT wrote:Venting a compressor is important. My last boat had the compressor in a side compartment and it got HOT. I'm sure it lowered efficiency.
My last boat had a cold plate retrofit, which worked very well, but the installer only added two little round vents, one of each side of a 'corner' structure, down low. Would have been much better if they used a rectangular vent up high. Even just one, as there are lots of little air leaks around the floor boards and hatch covers that are all part of the cavity. What kept it cool enough I suppose was all that hull in contact with the water and the big air space inside to spread that heat load around to more hull.

But if cutting in a vent or two, it would be better to put one high up to allow gravity venting of the warm air (rectangular), and nicer still to add another down low to allow gravity intake of cool air. Or a muffin fan for forced ventilation, tied into the compressor power, but to be honest, I suspect gravity venting would be adequate, and if battery power is critical, then maybe a 10W or so fan isn't such a good idea.

https://www.westmarine.com/buy/perko--o ... cordNum=41

Re: 12 volt cooler or refrigerator

Posted: Thu Jan 18, 2018 7:11 am
by BOAT
yes, it is the venting issue that I am struggling with right now - all the units require that the vents have adequate access to the air - that's a problem installing under a berth or something on a boat - it's a double whammy because the hot air also accumulates inside the compartment. (Man, now i know why old fashioned igloos are so popular).

It's a mod for a later day i guess - I need to noodle on this one for a long time before I attempt.

Re: 12 volt cooler or refrigerator

Posted: Thu Jan 18, 2018 7:59 am
by Ponaldpe
You do know that they make water cooled refrigeration units. But they would be no good on the trailer during trans port. Same with A/C for dry land camper use of the boat.

Re: 12 volt cooler or refrigerator

Posted: Thu Jan 18, 2018 8:18 am
by BOAT
Ponaldpe wrote:You do know that they make water cooled refrigeration units. But they would be no good on the trailer during trans port. Same with A/C for dry land camper use of the boat.
I have heard of those types of reefers and coolers - you need to throw a hose over the side for them to work - not really a big hassle if your staying in one place but not too practical for an ocean going vessel like 'boat' - we spend way too much time sailing to our destination (days) and I can't drag a hose behind the boat.

Also, the water in the Pacific is about 55 degrees on the surface minimum so you need a really long hose to get down to the cold water to make a refrigerator - but as a swamp cooler for an air conditioner it would work pretty good. All you need to do is pump the cold water into a radiator and blow a fan through it - a small bilge pump an fan would do it but the current draw needs to be compensated by something else to run it all day - I think one solar panel would probably do it.

Seems like a great idea to get A/C over here in SOCAL because we do not have real high humidity but really most people over here just take their clothes off. I do not know of anyone using one over here but i would love to hear a report from somebody who does have one.

Re: 12 volt cooler or refrigerator

Posted: Thu Jan 18, 2018 8:19 am
by Tomfoolery
BOAT wrote:yes, it is the venting issue that I am struggling with right now - all the units require that the vents have adequate access to the air - that's a problem installing under a berth or something on a boat - it's a double whammy because the hot air also accumulates inside the compartment.
What I noticed about the cold plate condenser unit on my last boat is that they oriented the fan parallel with the bulkhead (seat cushion support, just like the Macs) and they could have cut a vent opening with decorative grill and let the fan that's already part of the unit either draw in cool air or exhaust warm air (don't remember which way it blew). Some flexible cloth to connect the bulkhead to the heat exchanger would force it to replace air, though an additional intake or exhaust vent would be required to allow air to move.

The instructions for the unit may have prohibited using the fan to force air through a vent (thereby reducing the air flow rate through the heat exchanger), and I never looked into it (it worked fine, so I wasn't going to 'improve' it). But I remember thinking about it at least, and considering adding another vent high up, just below the horizontal seat support surface. Never did, though. :|

Re: 12 volt cooler or refrigerator

Posted: Thu Jan 18, 2018 8:28 am
by kurz
I never have concern if the sun shines on my Waeco compressor box...
If so - my 2x50w solar panel gets easily the juice for that :D take the money and hours in some solars... and your out...

Re: 12 volt cooler or refrigerator

Posted: Thu Jan 18, 2018 8:57 am
by BOAT
I wonder how many have considered expanding the fuel tank lockers on the M boat to accommodate coolers.

I dunno - it's still an issue I am noodling on - and right there in the back of the boat you have a great water jacket cooling system that could be used - (the ballast tank!) if you could just throw a shallow 4 inch high pan under the aft berth and put a couple of insulated doors on top of the pan I bet that area would stay pretty cold because it sits right on top of the ballast water! Throw in some ice and I bet it keeps for days? Put a drain hose from the pan to the shower bilge to accommodate the ice melting?

I dunno - I can tell you the key to discovering good mods is to let your brain go crazy - you really need to be a little bit nuts to engineer good mods - by letting your brain go wild you come up with all kinds of idea that don't work but those same ideas that don't work point you in new directions that DO work.

It helps to let go of your sanity for just a brief moment and just THINK.

Re: 12 volt cooler or refrigerator

Posted: Thu Jan 18, 2018 9:37 am
by K9Kampers
BOAT wrote:... I bet that area would stay pretty cold because it sits right on top of the ballast water!
I don't think so as the ballst water is only going to be as cold as the water outside the hull. During the summer in my sailing area, the ocean water, surface to approx 3 ft depth is typically 60 - 65°. The water certainly feels colder when swimming! I always have a thermometer in the water at anchor.

There's a difference between cold and cool. I bet the ales would be a lot colder if you dropped them overboard a few fathoms in a mesh bag. It's much chillier in the next thermocline!
BOAT wrote: I dunno - I can tell you the key to discovering good mods is to let your brain go crazy - you really need to be a little bit nuts to engineer good mods - by letting your brain go wild you come up with all kinds of idea that don't work but those same ideas that don't work point you in new directions that DO work.

It helps to let go of your sanity for just a brief moment and just THINK.
Agreed!

Re: 12 volt cooler or refrigerator

Posted: Thu Jan 18, 2018 9:46 am
by BOAT
There's a difference between cold and cool. I bet the ales would be a lot colder if you dropped them overboard a few fathoms in a mesh bag. It's much chillier in the next thermocline!
Yeah, now that's the thing, huh? I do the same thing with beer and soda before I throw it into the cooler - we store the soda cans in the boat dry because our little igloo playmate can't hold a lot, then when I'm running low on soda in the playmate I toss a six pack or some bottles into a mesh bag and lower it down deep into the water on a line (do NOT do this with a pack of hot dogs! We learned the hard way that the fish will eat ANYTHING that is not in metal or glass!) Then after a couple of hours in Davey Jones locker the warm bottles or cans are nice and cold and i can throw them into the playmate without melting all my ice.

The ballast tank by volume could never be effected by even several pounds of warm food - so I think it actually WOULD work as a better location for a cooler.

I just don't think it's a great place for the wife to try to retrieve sandwich meat or soda, but it might make a pretty good STORAGE solution that might work like the mesh bag?