Refrigeration: convert ice box or install under counter frig or drop in frig?

[Mr B]

Originally Posted by Shanaly

Alchemy - can you post details of peltier arrangement? I have plates, sinks, and power supply, and no reliable info source for sizing/matching and installation
J

I dont know if this will help you, But get onto Foretravel Owners Forum and look up the thread, Residential refrigerator,

They are currently discussing putting a house fridge in a Mobile Home,

RV's have the same electrical systems as boats,

My RV is only missing the solar panel of the roof, which will be installed when it gets here,
Then it will be the same electrical system that my Gemini has, Minus the wind generator,

Both my Gemini and my RV have been converted to 240 Volt power for OZ, But they are both still full 12 volt systems,

I also put a 12 volt, 5000 Watt 240 ac Invertor on my Gemini, Full pure sine,
$500-00 Delivered to Melbourne from China, Replacing my 1800 Watt Zantrax invertor, also made in China,

[sailorchic34]

Originally Posted by Richard Kollmann

Sailorchic 34,
I do not rule out dorm 110 volt refrigerators, there are applications where they are the best choice for boats that take only short cruises and spend most of the year connected to shore power. I can not see why your daily amp-hrs are so high with a three and a half cu ft box in San Francisco. The US climate zone average temperature report shows average temperature of 57 degrees F in 2012 and only one day did temperature reach 90 degrees. It is true that an increase ambient temperature of 90 degrees over 57 average degrees would double daily amp-hours consumed.

It is better to use watts of power into compressor to watts of energy out (Btu) when comparing Coefficient Of Performance (COP) than heat loss projections. The major difference between your 110 volt unit’s inefficiencies could be comparing a 110 volt inductance compressor motor against a three phase variable speed 12 volt compressor. Danfoss BD compressors can produce COP figures of 2.84 in a small drink cooler box when operated at 2000 Rpm. This higher COP is why box’s smaller than 4 cu ft operated in cool climates can consume 50% less daily amp-hrs than older Danfoss BD compressors.

Hi Richard, Good question..

Well I spend a great amount of time anchored out in the CA delta during the summer months, where the daytime highs can easily get into the upper 90's to low 100's in the summer. Though water temperatures in the high 70's moderate the inside boat temp to upper 80's to low 90's with a sun shade. So the amp draws I listed are for summers anchored out in the lovely hot delta and not the central bay. Look at Sacramento or Stockton weather data..

The Central bay is always cool as you indicate, which is why I'll spend months on the hook in the delta. In the central bay, the fridge run times are much shorter.

Agreed that the newer variable speed 12v danfoss compressor will have a better COP numbers. But for $200 I have a system that works at the dock and on the hook long term. I don't think that for a 90 degree f cabin temp that 2.5 amps per hour is all that bad.

[Pelagic]

I am considering the new 24Vdc drawer type as being the best use of space
Isotherm DR160 Double Drawer Refrigerator / Freezer

[Richard Kollmann]

Originally Posted by Pelagic

I am considering the new 24Vdc drawer type as being the best use of space
Isotherm DR160 Double Drawer Refrigerator / Freezer

Like all Recreational Vehicles appliances is this drawer unit structurally sound in rough seas. How would the process heat be disposed of? RVs have vents in exterior wall behind cabinet refrigerators.

[Sumner]

In addition to what Richard said....



That sure looks like it would spill a lot of cold air out every time you open it and the insulation doesn't look like much, especially on the front.

You are adding a lot of solar so maybe that doesn't bother you. It wouldn't work for us though,

Sum

[Mr B]

Originally Posted by Richard Kollmann

Like all Recreational Vehicles appliances is this drawer unit structurally sound in rough seas. How would the process heat be disposed of? RVs have vents in exterior wall behind cabinet refrigerators.

My Boat has a gas fridge, It has a vent at the back to let the heat out, Its externally vented into the cockpit,

[Badsanta]

The boat I had was a lp powered frig. When I moved it I found charred wood behind it. I replaced it with electric

[Irish rambler]

Fridges with a naked flame use the 'Peltier effect' and are not as efficient as a compressor fridge.
Have a look at truck accessory shops for 24 volt drawer fridges/freezers, you can also buy 'step ups' for 12v to 24v. The secret is in research and sharing your knowledge with others on this forum because all a dealer wants is a sale, your the one who has to live with it..
I have an Isotherm fridge and it's OK, nothing exceptional and even though installed meticulously, it's power hungry and spare parts are very expensive.
Check out shoreline-marine.co.uk for latest technology.

[Pelagic]

Originally Posted by Richard Kollmann

Like all Recreational Vehicles appliances is this drawer unit structurally sound in rough seas. How would the process heat be disposed of? RVs have vents in exterior wall behind cabinet refrigerators.

Valid points about securing, ventilation and efficiency. And I did look at that in making my final decision

When I bought the boat it had 2 x 24V Isotherm travel Boxes tucked in different places (One in hanging closet)
I brought both to pilothouse and made the freezer below and top (white) the drinks fridge)

Both had air-cooled Danfoss Compressors and being in Pilothouse, they were always well ventilated and never felt hot. Both are still working after purchase in 1998, but with rough guests break latching handles off I decided to replace.

First instinct was to replace, with same, but when I looked at new combo drawer systems realized I could increase total from 3.6 cu. ft. to 5.5ft Fridge/Freezer Capacity by integrating the drawer function

Room for added insulation, if needed as I will test first before fixing cabinet design.

This is a Marine model Isotherm with solid stainless sea latches.
Like any air cooled compressor, you need to install ventilation ducts top and bottom which I have allowed for.

Another plus is that the Bridge Aircon Box is just aft of it, so I can create even more ventilation by utilizing the A/C return. It also gives me a new serving counter for the bridge dinning, which is our most popular eating place when weather or bugs are not nice.

I find all else being equal… the efficiency of using a fridge is in the User. Keeping any fridge open when trying to find something is the biggest culprit.

I believe under-counter drawer types are more organized and stay open less time..

Oh yeah… and I did like the blue lights!!

DRAWER 160 INOX COMBO
The DRAWER 160 is a double-DRAWER set up, which offers both a
fridge and a freezer solution and additionally the great comfort of an
ice maker. The upper DRAWER of the new model 160 consists of the
refrigeration compartment with a 3,2 Cu. Ft volume while the lower
one combines a 2,3 Cu. Ft freezer and the ice maker with a 0,2 Cu.
Ft case for ice. The total internal volume sums up to 5,5 Cu. Ft while
the outer dimensions remain very compact. The DRAWER 160 can be
supplied either with 12v/ 24vdc, 230 V, 50 Hz or with 115 V, 60 Hz. It is equipped
with the frost-free concept, being extremely economical with electrical
energy and providing structural features which prevent ice accumulation
and therefore protect against increased energy consumption.
For an easy control of the temperature, a digital control panel is
positioned inside the upper DRAWER. The combination is equipped
with blue internal LED light.

[Badsanta]

Great looking system. Keep us updated!