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Ice Box Conversion

Nov 8, 2010
10,554
Beneteau First 36.7 & 260 Minneapolis MN & Bayfield WI
That's pretty impressive
Yep... 24 hour period average. But I have a pretty ideal set of conditions.
I have a rather small icebox, well insulated for its size.
Top opening.
I keep it full of beer. OK, some water
I'm on shorepower while at the dock, so its in ISEC mode when we push.
The compressor is below waterline in the bilge and has a huge vented locker to exchange air
We're very good about quick open/close. No hanging around with the top off.
 
Dec 28, 2015
476
Laser, Hunter H30 Standard Tacoma
Yep... 24 hour period average. But I have a pretty ideal set of conditions.
I have a rather small icebox, well insulated for its size.
Top opening.
I keep it full of beer. OK, some water
I'm on shorepower while at the dock, so its in ISEC mode when we push.
The compressor is below waterline in the bilge and has a huge vented locker to exchange air
We're very good about quick open/close. No hanging around with the top off.
How does having the compressor below the waterline help? Is it water cooled?
 
Nov 8, 2010
10,554
Beneteau First 36.7 & 260 Minneapolis MN & Bayfield WI
How does having the compressor below the waterline help? Is it water cooled?
No it’s Air cooled, supplemented by a DC fan. But the cooler the ambient air is, the less hard the system has to work to exchange heat. Being down in the relatively cooler air helps.
 
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Jun 3, 2012
546
Hunter 33 Bay Pointe, Quincy
Typical 12 VDC BD35 compressor draws about 3 Amps at low speed when running and up to 7 Amps at high speed. Most conversions of old ice boxes should expect about 50% running time. While there are many variables, it is best to plan around these values. Your fridge will probably be your largest battery load when you are anchored. Daily Amp/hours likely will be about 36.
 
Dec 29, 2008
697
Treworgy 65' Custom Steel Pilothouse Staysail Ketch St. Croix, Virgin Islands
We deinstalled our 110V Grunert and replaced it with a 12V SeaFrost a little over a year ago. We are exceedingly happy with the results. We added 300 watts of solar at the time. The boat sits on a mooring and the fridge is always on and sitting at 39 degrees. It sips energy, only running occasionally. Installation was straightforward. Solar powers it during the day and batteries at night. And our batteries: 2xDeka 4D gels, going on 11 years old and due (!) for replacement...
 
Feb 22, 2010
34
Oday 322 Delaware River
Hi all,
I concur with other posters here that the modern systems are MUCH more efficient. I installed an Isotherm system with the energy saving module. See my youtube video for the installation (press pause for the explanation screens) and the video comments for an extensive discussion on how it works, consumption, DIP switch settings etc. Very happy with it.

Based on watching the amp meter when it runs in 'economy mode', (2.5 amps) and estimating it runs 1/3 of the time per hour, that would be about 20 amp hours per 24 hour period.

 
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Likes: Jackdaw
Dec 28, 2015
476
Laser, Hunter H30 Standard Tacoma
I'm prepping to install 2 100 watt panels feeding a controller. Anyone have a good reference for the design side of the wiring? I'm needing input on how the controller should be wired up to my already existing system of 4 battery house bank with a 1000 watt inverter/charger and 55 amp engine alternator. From what I have come across it looks like you just wire it to the batteries.
 
Jul 1, 2010
674
Seaward 25, Catalina 350 Ithaca, NY
Yes, however you need to choose your wire size based on the maximum current your controller can put out and your desired voltage drop between it and the batteries. Then you will need to fuse the wiring at the batteries with a fuse sized to protect the size wiring you chose. If you have multiple banks you are trying to charge, you'll also have to have a combiner or isolator between the banks. I believe Maine Sail has a lot of info on this on his Compass Marine site.
 
Jan 11, 2014
4,057
Sabre 362 113 Fair Haven, NY
I'm prepping to install 2 100 watt panels feeding a controller. Anyone have a good reference for the design side of the wiring? I'm needing input on how the controller should be wired up to my already existing system of 4 battery house bank with a 1000 watt inverter/charger and 55 amp engine alternator. From what I have come across it looks like you just wire it to the batteries.
There is a maximum number of connections on each battery post, that number is 4. With the alternator, house wiring, inverter, and parallel/series wiring you are at that limit. Time to add positive and negative bus bars to the system to free up room on the battery posts. Check out MarineHowTo.com that's MaineSails site and also check his forum here on SBO.
 
Jul 1, 2010
674
Seaward 25, Catalina 350 Ithaca, NY
In addition to what was said in the above post, where are your current charging sources attached. Directly to the batteries? Or do they all go to the common post on a 1, 2, both switch, or a combination of both. This will help determine how you want to connect your solar charging. You might find that it's time to rethink how everything is wired. Again, lots of info and discussions on this on the Maine Sail forum here, and on his Compass Marine site.
 
Jan 11, 2014
4,057
Sabre 362 113 Fair Haven, NY
Rule # 1 in boat repair, maintenance and upgrades: It is never as simple as it sounds.
 
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Dec 28, 2015
476
Laser, Hunter H30 Standard Tacoma
Yes, however you need to choose your wire size based on the maximum current your controller can put out and your desired voltage drop between it and the batteries. Then you will need to fuse the wiring at the batteries with a fuse sized to protect the size wiring you chose. If you have multiple banks you are trying to charge, you'll also have to have a combiner or isolator between the banks. I believe Maine Sail has a lot of info on this on his Compass Marine site.
I'm going to use 8 awg which is way over sized for the two panels and length of the run but the controller is 40 amp so I want to plan ahead for expansion. Fuses will be installed appropriately. I have a 4 battery coach bank and a single starter battery that has a isolator. I'm heading to the Maine Sail site to take a look see. Thanks for the input!
 
Dec 28, 2015
476
Laser, Hunter H30 Standard Tacoma
In addition to what was said in the above post, where are your current charging sources attached. Directly to the batteries? Or do they all go to the common post on a 1, 2, both switch, or a combination of both. This will help determine how you want to connect your solar charging. You might find that it's time to rethink how everything is wired. Again, lots of info and discussions on this on the Maine Sail forum here, and on his Compass Marine site.
I'm heading to the boat tomorrow to trace everything out. I'll get back to you with what I found out. Mapping out the electrical system has been on my list for a while. This gives me a good reason.
 
Jun 9, 2004
615
Catalina 385 Marquette. Mi
Yep... 24 hour period average. But I have a pretty ideal set of conditions.
I have a rather small icebox, well insulated for its size.
Top opening.
I keep it full of beer. OK, some water
I'm on shorepower while at the dock, so its in ISEC mode when we push.
The compressor is below waterline in the bilge and has a huge vented locker to exchange air
We're very good about quick open/close. No hanging around with the top off.
You forgot to mention 50dg Lake Superior water....
 
Apr 7, 2016
183
Beneteau First 305 Seward, Alaska
I may get laughed out of here for this... as a mostly day/weekend sailor, just spend a couple hundred dollars on a dorm fridge and maybe an inverter if needed. Unplug when you leave the dock with a full rack and/or cool a few drinks a day while you’re running your engine charging your battery at anchor.
 
Dec 28, 2015
476
Laser, Hunter H30 Standard Tacoma
I may get laughed out of here for this... as a mostly day/weekend sailor, just spend a couple hundred dollars on a dorm fridge and maybe an inverter if needed. Unplug when you leave the dock with a full rack and/or cool a few drinks a day while you’re running your engine charging your battery at anchor.
If I was going to just day sail and use it as a cooler when of off 120vlt.
 
Apr 7, 2016
183
Beneteau First 305 Seward, Alaska
If I was going to just day sail and use it as a cooler when of off 120vlt.
Yeah that is what I meant. But after a day or so it will be warm. Thus the inverter to cool it back down when you’re charging your batteries.
 
Dec 28, 2015
476
Laser, Hunter H30 Standard Tacoma
Day one the install complete. Total time of approx 3 hrs. Evaporator installed in the ice box, compressor mounted in the lazaret. Cooling circuits connected, control mounted on the bulkhead ( not in the icebox). Tomorrow is install the power circuit to the panel and 15 amp breaker, seal up the hole then enjoy cold refreshments.