Refrigeration

[dlockhart]

We recently went from a small 12V with a light and little freezer to a larger stand up that works on propane, 120V ac or 12vdc. No moving parts to wear out, uses the energy to heat helium or hydrogen that pushes pneumonia through the system and is somehow condensed and gives up heat. Very old technology that was in refridgerators that lasted 40 years or more.
We run propane during the night when the thing is not being opened and 12V during the day when the sun is out, 120V when at the marina.
Old fridge works great but is small and taking up room in my truck, would like to sell to someone who would like a fridge that uses about 4 amps at 12Vdc when running.

[ranger58sb]

Originally Posted by Cheechako

Question: is it true that all compressors are 120v? I guess they used to be, and I thought that the newer Danfoss type were now actually 12v, but in another thread a while back I thought someone indicated they were still 120v motors..?

I'm told by our fridge maker that the compressor in our units are 12v. Both fridges run on either AC or DC, but when fed AC its simply converted to DC first as with many other small appliances, computers, etc.

Jim, you'll see some electric installations are AC only, and one either runs the genset or uses an inverter when away from shorepower. Others, like ours are both AC and DC, so we can run on batteries (DC) while underway)... or we could use the genset (or inverter, if we had one) while underway. I'm not aware of an DC-only units, but there may be some. In any case, I expect there are pros and cons to each type of unit.

-Chris

[Cheechako]

Originally Posted by dlockhart

We recently went from a small 12V with a light and little freezer to a larger stand up that works on propane, 120V ac or 12vdc. No moving parts to wear out, uses the energy to heat helium or hydrogen that pushes pneumonia through the system and is somehow condensed and gives up heat. Very old technology that was in refridgerators that lasted 40 years or more.
We run propane during the night when the thing is not being opened and 12V during the day when the sun is out, 120V when at the marina.
Old fridge works great but is small and taking up room in my truck, would like to sell to someone who would like a fridge that uses about 4 amps at 12Vdc when running.

I hope it isn't contagious!

[deckofficer]

For large, front door fridge and freezers I'm surprised no one has mentioned Sun Frost. High end yacht builders use them along with the intended market, off grid homes. I don't know of any this large that are as efficient.

Refrigerators, Home Compost Bins, Composting Toilets and Sustainable Living Products - Sun Frost

[skipmac]

Originally Posted by meridian28

We are using a Dometic RV propane/110v unit. Uses about a 20# tank every 3 weeks.

Good friend has a propane fridge in his camper and loves it. The problem is they don't work beyond a certain angle so not practical for a monohull at sea. Power boats and cats would be fine.

[a64pilot]

Originally Posted by skipmac

Good friend has a propane fridge in his camper and loves it. The problem is they don't work beyond a certain angle so not practical for a monohull at sea. Power boats and cats would be fine.

I've got one in my 5th wheel too, and it works just fine going down the road at different angles, and accelerations etc. as those are transient, what will ruin one is sitting for some time un-level, the fridge is what makes leveling an RV important, running one when it's not level will apparently ruin it, maybe even heeled over is not a constant angle, maybe it's enough variation to not cause damage?

[dannc]

Originally Posted by deckofficer

For large, front door fridge and freezers I'm surprised no one has mentioned Sun Frost. High end yacht builders use them along with the intended market, off grid homes. I don't know of any this large that are as efficient.

Refrigerators, Home Compost Bins, Composting Toilets and Sustainable Living Products - Sun Frost

Bob,

I was about to mention SunFrost! They pull some very small DC power loads and I was wondering if they were used in a marine environment, and if not, why? This page has lists more brands of fridge/freezers that use DC, http://www.backwoodssolar.com/produc...e-goods?cat=51.

I was also looking Miele marine units which seen to have minimal AC usage, Miele Marine though I would be the cost of the units is high.

Later,
Dan

[deckofficer]

Originally Posted by dannc

Bob,

I was about to mention SunFrost! They pull some very small DC power loads and I was wondering if they were used in a marine environment, and if not, why? This page has lists more brands of fridge/freezers that use DC, Appliances - Products.

I was also looking Miele marine units which seen to have minimal AC usage, Miele Marine though I would be the cost of the units is high.

Later,
Dan

The last couple of Chris White Atlantics are using Sun Frost.

[belizesailor]

Originally Posted by Captjimmy

Having lived on a sail boat with its small hole in the countertop refrigerator, we were always envious when visiting trawlers and seeing what appeared to be gigantic stand alone refrigerators and freezers. Contemplating trawler life and would like to know the pros and cons of these large refrigerators for a couple living aboard and favoring the hook vs the dock.

Jim

Both Dometic and Sun Frost, and probably a few others, make efficient larger fridges.

I used to have a Dometic that was near full sized at home (off grid) and have run boats with the same fridge. Draw is more than a small DC fridge of course, but not bad. Mine would draw about 5A @ 12VDC when cycled up. Exact specs on Dometic site.

[Dauntlessny]

I just swapped out my 120v Fridge and Freezer for 12v (really variable, 12, 24, 120 or 240v) Vitrifrigo fridge and freezer. I opted for the fridge that has the small freezer compartment in in as that model also had the external Danfoss BF35 compressor (same as freezer).

So far, they seem to average 5 amps, 60 watts, per hour.

With the addition of 440 watts of solar panels, it has totally transformed the electrical load on the batteries. I hope to never run the Gen again!

[Hudson Force]

Has anyone here with a technical background evaluated the application of the very small Aspen rotary 12VDC compressors for use in marine refrigeration? I've only read the glowing reports from the developer and manufacturer. I'd like to hear something critical and unbiased, but I'm always ready to embrace something new that works well.

[dlockhart]

LOL, pneumonia! I must have been thinking of what I'm catching while up here in Canada visiting our kids and new grandson. Good catch!
Our fridge is a Dometic european model of around 8 cubic feet as I recall and in automatic it chooses the most efficient power source with 120V first, propane second and 12V third unless it senses enough voltage from the solar panels then it switches to 12VDC.
The old, little fridge has a compressor in it, Danfoss I think, that I thought was 12vdc and I don't recall seeing an inverter on it when I pulled it out. It used less amps than the newer one on 12V but the new is twice the size but only uses 2 more amps at most. I didn't vent the new one to outdoors, I vented from through the floor from the bilge area on the starbord hull around the rear of the unit and it vents out into the galley at the top. We only use the propane when anchored out and at night and the ports and hatches are always open for air. I also installed a propane / carbon dioxide sensor at the floor level right beside the unit. Heat coming out the upper vents is minimal and so far we are liking the whole deal.

[Captjimmy]

Thanks for all of you replying to my post re: Refrigeration. As with all things in boating compromise, compromise, compromise!

JIm