A Real DC Refrigerator

[DLT]

the original source you pointed to says 750 watt hours per day.

I don't know where you're getting that number from. But, from the link (about 2/3 of the way down), they claim, "[a]s supplied the R4500 uses 480 watt hours / day". They also claim "[s]ingle door models consume about 35 watts when compressor is running: under 3 amps 12 volt". So, they are estimating about a 57% duty cycle. The numbers you are using are up near a 75% duty cycle. But, that's probably more realistic for a really hot day anyway...

Ultimately, I agree that a refridgerator probably doesn't make a whole lot of sense for the typical trailer sailor, especially if you don't have a ready source of AC power to charge the batteries.

With that said, I absolutely love mine. I bought it off ebay for "a whole lot of ice"... IIRC, it was well under $600 with shipping...

Of course, my boat is slipped with shore power. So, charging batteries for a day out on the water is a trivial issue, for me.

I don't leave the fridge running between weekends, so it takes the Friday evening/night to cool down. So, I typically bring things down to the boat in a cooler with a bag of ice...

[Chip Hindes]

I don't know where you're getting that number from

.

From the link to the website which you provided.

SUNFROST products have 4 to 6 inch insulation, and the compressor is on top where it cant put heat back into the box. The RF-16 model uses a total of 750 watt hours a day, about 300-400 watts of solar modules, depending on the climate.

NOVAKOOL products are smaller DC powered refrigerators made for RV & marine markets. With the same Danfoss compressor as the Sunfrost, these are smaller refrigerators but use about the same power. Adding 2 extra inches foam insulation to all surfaces except the door cuts that power use in half.

[DLT]

Whoa there hoss, not that I provided...

Anyway, come-on, lets compare apples to apples. The RF-16 is a "[t]wo door unit [that] has 3.9 cu ft freezer and 10 cubic foot refrigerator". In contrast, the R-4500 unit, that was actually asked about, is just a basic 4.3 cubic foot unit...

Yes, it looks like those larger sunfrost units are more efficient for the cooled space, but at an astronomically higher cost...

Heck, they also say that if you add 2" of insulation all the way around, on the R-4500, you might cut your power draw in half...

[Idle Time]

the only problem with the Thermo-electric coolers is they cool to 40 deg below current temp....if it's 100 in the boat....that's only 60 in the cooler...not cool enough for meats etc.

[DLT]

That's why we are discussing real DC refrigerators with compressors...

They aren't cheap, and as Chip points out, cost a whole lot of ice and require a good source of power (if only to keep that batteries charged).

But, to me, mine has been worth it...

[Bobby T.-26X #4767]

i love my Engel.
it's 75 outside and 39 inside as i type.
i know this because i purchased the external LCD thermometer. it's mounted in the cabin.
i've got the unit set on #1 (refridge), yet it goes to #5 (deep freeze).
i'll use it this week in my X while mounted under the rear dinette seat.
then, i'll place it in the rear end of my mini-van to use for daily shopping.
it keeps ice cream frozen or regular groceries chilled even when it's 120 inside the vehicle.
mine ended up being $617 (included shipping and no tax) from "Compact Appliance" out of Texas via the internet.
it's the best solution.

Engel 35






BTW...still "borrowing" wireless from an unknown source at the Channel islands marina.

[Night Sailor]

There are 12v dc timers that can be added to a power circuit to determine the run time on thermo coolers. I may install one for our 32 qt. Koolatron Kargomate, though my present hot weather system of precooling it, adding only frozen food or water to it, surrounding with insulation, opening only two times a day, and turning it off while sleeping, and during meals, has worked so far. The total cost for cooler, batter saver, AC adaptor, was less than $200 and it does the job for our tastes. The best thing is it's portable for parties, BBQs, beach picnics, offroading, and long car trips. It only weighs about five pounds. I do have two house batteries and a solar charger to keep them topped when the engine isn't used. It's been totally reliable for the last four years of heavy use. Both for cooling, and for keeping things from getting frozen in CO winters.

[Captain Steve]

Bobby T, Been down several times to see you. Noticed your last post was at 8:22....I was there at 8:15. Will try at noon, eating my lunch down there

[Bobby T.-26X #4767]

Steve,
enjoyed sharing war stories this afternoon.
i believe that the time stamp is "central". that is, where ever Heath lives.
am i correct?

[Frank C]

The "time posted" is determined by each member's profile entry. When you sign-on as a member you enter a timezone ... e.g. [GMT -8hrs] for the Left Coast. Regardless of your physical location when you enter a post, it will be time-stamped as if your are at the home timezone you selected when you became a forum member.

[Bobby T.-26X #4767]

The "time posted" is determined by each member's profile entry. When you sign-on as a member you enter a timezone ... e.g. [GMT -8hrs] for the Left Coast. Regardless of your physical location when you enter a post, it will be time-stamped as if your are at the home timezone you selected when you became a forum member.

yes, got it.

BTW Frank C, you'd love the Engel. it works great and uses very little power once it's chilled.
i'll post my mod to the rear seat tub. I used a 3.5" hole saw to allow for ventilation. wasn't nearly as involved are Eric Hardle's Mod for the same unit. took just a few minutes.
then all you need is a DC outlet near the location.

[Frank C]

Im sure you're right, but for 2 issues ...
Primary - my boatbucks are allocated elsewhere, and the 5-day cooler seems okay for current needs.

Secondary - the cooler tub sleeps w/ the fishies ever since the 5-day cooler arrived.

[Bobby T.-26X #4767]

Secondary - the cooler tub sleeps w/ the fishies ever since the 5-day cooler arrived.

??? i guess it's a joke, but i don't get it...
you mean you threw it overboard into the ocean?
now why would you do a thing like that?

BTW...i got tired of this scenerio:
- i live 20 minutes from the marina and dry store my X. so when i launch, i keep at the guest slips for 4-7 days at a time
- i might sleep at home a day or two during the week while the X is in the water and am always worried about the cooler. enough ice, what's in there that might spoil, gotta freeze another jug and take it with me? you know the drill.
- now, no more worries.

that is, i'd rather spend 600 boat bucks on an Engel that i can use all the time, then on a new GPS (Duane's special deal) that i can only use when i'm in my X.

but hey! different strokes for different folks...

[pearl372]

ModsNote: Date changes here . . . resurrecting old thread ~fc

To those of you with the Engel 35 stored in the former cooler, albeit modified with cutouts. Do you keep the wood panel and cushion seat on top of it for extended periods while the Engel is powered on? Has it overheated? Also, I have shore power but no outlet nearby. I do have a DC outlet. Any problem with powering the Engel from the DC outlet while the battery is being charged via shorepower?

Thanks.

Rob

[Chinook]

I didn't like the idea of placing the unit in the stock fiberglass box, even with cutouts. By placing it directly in the bilge, air circulation is much better, and the below waterline airspace helps cut down on the work the frig needs to do, at least when sailing in cooler waters. I made a flat, level platform in the bilge, on either side of the ballast tank, by shaping blocks of styrofoam. This gives a nice non skid platform for the frig to sit on. I cut out and installed louvered vents under the table and in the head, in line with the compressor vents, to further help the ventilation. I wrapped the food box part of the unit with sheets of 2 inch insulation, which help retain the cold. The lid sits about 3/4 inch below the flat panel. I glued a pad of closed cell foam to the underside of the panel, and the panel sits directly on the lid, making it nice and firm, with the cushion on top, and adding even more insulation. I didn't like the idea of plugging into a 12 volt receptacle, thinking it was subject to poor contact and voltage loss. Instead, I ran the 12 volt cord to the house batteries, cut the receptacle off, and wired directly onto the batteries. A simple in line fuse holder provides protection. Forget about using the thermal fuses that come with the unit. They're expensive and polarity sensitive. If installed the wrong way they pop. Standard glass fuses from the auto parts store work fine. We love the unit. Wired and insulated like I did, it's very efficient.