Seeking Fridge / Ice Box Advice

[nautical62]

I recently purchased a used 88 Hunter 30 that I will be using mostly for Bahamas cruising of cruises to 3 months duration. The built in ice box is enormous and had been converted to a fridge with a norcold unit. However, the compressor was broken and seems to be not worth fixing. In addition, the icebox has not been reduced in size and appears to have little or no external insulation (can't get at it, but there is clearly little room.).

Having at least some refrigeration or cooling ability is fairly important to me, so I'd love to get some feedback on options I may have.

It seems to me, it's not worth replacing the norcold unit unless the icebox is reduced in size and properly insulated.

My current thought is to keep using the ice box as an icebox, adding some interior insulation and also add a small cooler/compressor stand alone unit such as the one at the link below. My thought is when I hit town, get some ice and live it up for a couple day with all sorts of fresh stuff, but once the ice melts, just keep the basics cold in the cooler/compressor.

Considering the boat will only be used for a maximim of 4 months cruising per year, I'm also a bit tempted to just go with ice., but I really do enjoy having a minimal amount of refrigeration capabilities, even if it's just cream for coffee, a little ice and a few cold drinks. I'm frequently away from ice purchasing ability for 7 to 10 days at a time.

Energy - I currently have no solar or wind. The only charging is from the alternator. Unfortuanately I don't have it's output available at the moment. The boat has two batteries I believe with 120 AH each, but one will be reserved as a starting battery at least at night. I have room to add another. My cruising style is so that I don't sit long at anchor and move and use the engine most days, but unless I have energy needs, my engine time is often minimal.

When I read some of the literature on the compressor/cooler unit, it said typical energy consumtion was 2 AH. However, I have no idea what this is based on. I don't know if this means when it runs, but doesn't run all the time or this is an average per 24 hours of running in moderate climates - makes a big difference.

The shelf I would put this on would allow good ventilation of the compressor into the cabin. Exterior ventilation would be difficult. I have room to add some additional exterior insulation and still allow the vents to vent properly.

I'm experienced with epoxy work so could do a reasonable job of reducing the interior space in the current icebox to convert it to a refrigerator, but I'm not sure I'll have the time prior to my first big cruise. A mentioned previously one side wall would be difficult to add insulation to. In addition the cooler/compressor meets my space needs for about half the price. I should note that the top door to the ice box is right on top of one of the sidewalls, making it impossible to add any significant insulation to that side wall without a major countertop and door project.



Any experiences with these cooler/compressors or this in general are greatly appreciated.



The unit type I'm considering though I may go smaller:

West Marine: Compressor Cooler AC/DC Product Display

[mesquaukee]

The unit uses 45 watts of power or 4 amps at 12 volts ( 2 amps at 24 volts)
According to the manufacturer at an air temp of 30C or 86F it runs 35% of the time with the interior being 5C or 40F.
What this means is just keeping things cold, ie not making ice you will use 35 AmpHrs a day of energy. Without knowing your current energy budget it would be difficult to sy if you needed to expand you battery bank. My gut says you will as your sole source of electricity is the engine.

COOLMATIC CF-50 50L PORTABLE FRIDGE/FREEZER Specifications

• Temperature range: +10°C to -18°C
• Thermostatic control
• 50L capacity
• 360mm W x 480mm H x 630mm D
• Weight: 18 Kg
• Power input: approx. 45 watts
• Running time per hour at 5°C interior temp: 20°C ambient temp = 25%
• 30°C a.t. = 35%

[Portobello]

I will be interestes in this thread also - I have a large ice box also and have contempleted adding an electric eutectic sysyem to it. My alternative is also to buy one of those portable Engel units and use that. A mate of mine installed one of those compressor type units to his ice box and was very happy with the results.
I can afford 2 or 3 amp over 24 hours with my set up but would have to charge if it isnt sunny.

[nautical62]

Originally Posted by mesquaukee

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COOLMATIC CF-50 50L PORTABLE FRIDGE/FREEZER Specifications

• Temperature range: +10°C to -18°C
• Thermostatic control
• 50L capacity
• 360mm W x 480mm H x 630mm D
• Weight: 18 Kg
• Power input: approx. 45 watts
• Running time per hour at 5°C interior temp: 20°C ambient temp = 25%
• 30°C a.t. = 35%

Great info - can you tell me where this came from? I'd like to see the specs on the 35L model as well. I can live without making ice and the power use seems reasonable.

[mesquaukee]

Originally Posted by Portobello

I will be interestes in this thread also - I have a large ice box also and have contempleted adding an electric eutectic sysyem to it. My alternative is also to buy one of those portable Engel units and use that. A mate of mine installed one of those compressor type units to his ice box and was very happy with the results.
I can afford 2 or 3 amp over 24 hours with my set up but would have to charge if it isnt sunny.

If your primary energy source is solar do not use eutectics or a cold holdover plate system. They use about twice as much AmpHrs/day for the same box temperature. They are also heavy and take up a lot of space.

The only reason to use eutectic or cold holdover plates are if you have a genset or regularly run your engine which has the compressor on mounted on it.

The most efficient systems are ones using evaporator plates and a TX valve.

[mesquaukee]

Originally Posted by nautical62

Great info - can you tell me where this came from? I'd like to see the specs on the 35L model as well. I can live without making ice and the power use seems reasonable.

It is at Buy Cheap COOLMATIC CF-50 50L PORTABLE FRIDGE/FREEZER - Reviews UK

[Portobello]

I was always under the impression that the evaporator plate ones were very slow to cool and struggled to maintain low temps. Cruising around here I would run the motor every day and keeping the batteries topped up does not seem to be a problem- it has a big alternator!

[mesquaukee]

Found the CF 35 and others its, Waeco Coolmatic CF Cool Freeze Compressor Coolers Fridge & Freezer Cool Boxes 12 24 Volt

Coolmatic CF 35
Average power consumption: 45 watts Average running time at 5°C: 15% at 20°C ambient temperature 19% at 32°C ambient temperature

Coolmatic CF 50
Average power consumption: 45 watts Average running time at 5°C: 10% at 20°C ambient temperature 15% at 32°C ambient temperature

The numbers are different than the other site. Also the CR35 runs longer even though it is smaller.
I think the numbers for the cf 50 are a missprint.

[mesquaukee]

Originally Posted by Portobello

I was always under the impression that the evaporator plate ones were very slow to cool and struggled to maintain low temps.

It all depends on the care taken in the design of the system, the selection of the size of the compressor and the placement of the components.

There are a lot of misconceptions about 12 volt systems. The smaller, inexpensive (relative to other 12 volt systems) do it yourself kits have unfortuantly perpetuated this belief.

[mesquaukee]

Originally Posted by mesquaukee

Found the CF 35 and others its, Waeco Coolmatic CF Cool Freeze Compressor Coolers Fridge & Freezer Cool Boxes 12 24 Volt

Coolmatic CF 50
Average power consumption: 45 watts Average running time at 5°C: 10% at 20°C ambient temperature 15% at 32°C ambient temperature

The numbers are different than the other site. Also the CR35 runs longer even though it is smaller.

I believe based on box size etc. the above is a misprint and should read as in an earlier post as,
Average power consumption: 45 watts Average running time at 5°C: 25% at 20°C ambient temperature 35% at 32°C ambient temperature

[Dockhead]

That ought to be a great unit. Note that it is a conventional compressor and evaporator based system, and not a power-hogging thermoelectric system like most picnic coolers. See: http://www.dometic.com/3c285831-c021...02c1ac02.fodoc

It has temperature readouts and sophisicated controls. Needs no raw water supply or plumbing. Other than the fact that air-based condensors are less efficient than water ones, this should be about as efficient as you can get, besides a totally no-hassle plug-and-play installation.

[nautical62]

Originally Posted by Dockhead

That ought to be a great unit. Note that it is a conventional compressor and evaporator based system, and not a power-hogging thermoelectric system like most picnic coolers. See: http://www.dometic.com/3c285831-c021...02c1ac02.fodoc

It has temperature readouts and sophisicated controls. Needs no raw water supply or plumbing. Other than the fact that air-based condensors are less efficient than water ones, this should be about as efficient as you can get, besides a totally no-hassle plug-and-play installation.

Those characteristics fit my situation well. Thanks for the link.

Does anyone have any experience or thoughts about the drawer unit on the bottom of the above linked page? It would fit my space prefectly and appears to be run by the same compressor and have a similar energy draw to comparible cooler style units. I image one looses more cold air when opening a drawer, but are there any other trade-offs I should be aware of?

[Rhosyn Mor]

A couple of thoughts;
keep your ice box as an icebox, get some very high quality insulation and use double the recommended thickness, Ice should keep for 5/6 days.
for milk/ cream use NIDO.
a mesh bag hung over the side and dropped 10 feet down will keep soda pop cool, and white wine . if you run the drain from the ice box into a bucket you will have ice cold water to flash cool drimks.

[Pblais]

You could add insulation to the inside of the fridge since it is so large. If you then made a liner for it it would then be a suitable well insulated fridge. You can also then add a divider and make a spill over fridge and while not a great freezer it could keep items frozen that were already frozen.

A do it yourself fridge kit is about $1100 more like $1300 for a cold plate unit. They come with a 15 ft refrigerant line that can be led to the compressor where it would be properly connected up. That would make 6 to 9 cubic feet or about 170 to 250 liters. That is enough to go places.

I've done the past two years with ice and it is fine for short trips of 4 days or less. It does get to be a problem when you go longer and want to carry more food. Long term the cost of ice is significant given you get so little back. Having had a fridge previously I'm convinced. The fridge parts arrived this morning.

FWIW, you don't usually fix an old fridge at least for very long. The modern ones if well installed can last maybe 18 years. If you have the batteries and the charging system then adding a fridge makes good sense.

[nautical62]

Originally Posted by mesquaukee

I believe based on box size etc. the above is a misprint and should read as in an earlier post as,
Average power consumption: 45 watts Average running time at 5°C: 25% at 20°C ambient temperature 35% at 32°C ambient temperature

Thanks - great comparison chart there. The 50 clearly looks off.