Upgrading Battery Bank & Refer Unit

[MIRELOS]

You're right, should read all next time

[Typhoon]

Originally Posted by MIRELOS

You can see what boat I have under my posting name, as well as my location.
I do have solar panels and a wind generator for when off the grid.
This last weekend I was "unplugged and it all worked excellently, the power consumption of the ColdEh units is very low, my batteries were 100% charged throughout the day (solars) and at night they went down to 98% and quickly came up to !00% with the sun.
The Eleuthera is a big boat with a lot of power demands that's why I made the changes.

Hi Mirelos.

We are very happy you like your new systems. It was a pleasure to help you get ready for your escape south. Hopefully we will be visiting you there in the not to far future .

That original setup with with all the water cooling pumps and strainers was a mess, times three. Now no more maintenance ! Our simple TXV based air cooled systems will only need a dusting once a year, and serve you well, enjoy.

Regards John
www.coldeh.com

[a64pilot]

Originally Posted by Richard Kollmann

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The advice given to use an Engel portable as your freezer has been followed by many satisfied boaters.



Kollmann Marine

In fact there is a lot of logic in Nolex’s system, just use portables and don’t have a built in system.
Makes servicing a non issue and they are far less expensive and much, much easier to replace when the time comes, and are not inefficient, plus you have a backup if one goes down, and in times when you don’t need both a freezer and a fridge, unplug one and save the power.
I had considered it but didn’t cause I have a huge icebox and to put portables there would require a lot of carpentry work, that I didn’t want to undertake. Other than that, there seems to be no downside to portables that I see.

[CGirvan]

Just wondering how the portables can be so efficient when they only seem to have a couple of inches of insulation. The one thing that everybody here seems to agree on is the importance of adequate insulation.

[Typhoon]

Originally Posted by CGirvan

Just wondering how the portables can be so efficient when they only seem to have a couple of inches of insulation. The one thing that everybody here seems to agree on is the importance of adequate insulation.

They are not really all that efficient when you compare them to a well insulated built in box .

Lets go through the number .

A 43 quart or 1.4 cubic foot Engel MT45. will use at the minimum, .7 of an amp . So that is .7 of an amp for 1 .4 cubic foot of space. times that by 24hrs and you have 16.8 amps in 24 hours .

Our 7 cubic foot R30 refrigerated box on our boat averages 11 amp hrs per 24 h.

7 cubic feet would equal 5 Engel fridges to have the same volume , so 5 x 16.8 amp hrs or 84 amp hrs in 24 hrs.

Not so efficient when you put it into the right context.

Regards John.
www.coldeh.com

[newhaul]

Originally Posted by ColdEh Marine

They are not really all that efficient when you compare them to a well insulated built in box .

Lets go through the number .

A 43 quart or 1.4 cubic foot Engel MT45. will use at the minimum, .7 of an amp . So that is .7 of an amp for 1 .4 cubic foot of space. times that by 24hrs and you have 16.8 amps in 24 hours .

Our 7 cubic foot R30 refrigerated box on our boat averages 11 amp hrs per 24 h.

7 cubic feet would equal 5 Engel fridges to have the same volume , so 5 x 16.8 amp hrs or 84 amp hrs in 24 hrs.

Not so efficient when you put it into the right context.

Regards John.
www.coldeh.com

john sorry but that logic doesn't really hold up . If I put one of your units in a 1.4c.f. Icebox conversion it will still use the same amount of energy that it does in 7c.f. Which means it uses a bit less power but for about triple the insulation.

[newhaul]

Originally Posted by CGirvan

Just wondering how the portables can be so efficient when they only seem to have a couple of inches of insulation. The one thing that everybody here seems to agree on is the importance of adequate insulation.

its mostly due to the energy efficiency of their swing compressor. ( which is only good for up to about 3.5 c.f. In my experience)

[CGirvan]

Originally Posted by newhaul

its mostly due to the energy efficiency of their swing compressor. ( which is only good for up to about 3.5 c.f. In my experience)

Is this compressor used by engel alone or do all the manufacturers of these portables use them?
Are they available for sale?

[Typhoon]

Originally Posted by newhaul

john sorry but that logic doesn't really hold up . If I put one of your units in a 1.4c.f. Icebox conversion it will still use the same amount of energy that it does in 7c.f. Which means it uses a bit less power but for about triple the insulation.

Sorry yes it does . If I only used 1 inch of insulation in a 7 cubic foot box the amp hrs would go through the roof .

Also I used the minimum amperage stated by Engel which is .7 to 2.5 amps

Its all relative. The more space you cool the more power it will take to do it . Insulation is the determining factor when you get into more cubic feet. So if all you need is 1.4 cubic foot of space , then get a portable , but don't compare them to a well designed and insulated built in box.

Regards John
www.coldeh.com

[Richard Kollmann]

My 24 hour testing of the Engel 45 in a controlled 80 degree F test area at a -2 degree freezer temperature had exceptional insulation. The exterior insulation showed only a 4 degree delta T against 80 degree ambient air.

[CGirvan]

Originally Posted by Richard Kollmann

My 24 hour testing of the Engel 45 in a controlled 80 degree F test area at a -2 degree freezer temperature had exceptional insulation. The exterior insulation showed only a 4 degree delta T against 80 degree ambient air.

What thickness of insulation does the Engel 45 have and does anyone know what they use for insulation.

[Copacabana]

Originally Posted by CGirvan

What thickness of insulation does the Engel 45 have and does anyone know what they use for insulation.

I have the Engel 40 drop-in model and it is closer to 3 inches of insulation. I don't know what they use for insulation.

Mine sips amps, but it's also only a 40 quart box. It's a small fridge. I think the advantages of an Engel are its simplicity (it's a ready kit - plug and play) and the ease to replace it, should it fail.

[a64pilot]

The Engel is not really all that efficient, mine runs quite a lot, but I am using it as a freezer, it’s cold -5f and it sweats if you put anything on the top and whatever it sits on will get wet too, so it sits in our second head on the floor. It insulated with an expanding foam, there is a warning about it on the bottom of the box, I think it emits a poisonous gas when it burns or something, or maybe you just shouldn’t eat it
The Sawafugi swing compressor isn’t any more efficient I don’t think than a a Danfoss type, in fact I’d bet the variable speed Danfoss is more efficient. Swing compressor is a neat design, uses the natural harmonic frequency of a spring as its operating principle, sort of like pushing a kid in a swing, Time it just right and you can push the kid quite high. It is a sort of soft start due to this principle too, cause you have to push several times until you get the kid really swinging. It uses a spring instead of gravity, and a piston is the kid.
It’s not that the Engel is so good, it’s that most of our old ice boxes are so bad.

See that is sort of the thing, everyone pretty much has to use the same compressor, so about all that can be done from one manufacturer to the other is quality parts that are well matched, so if they are all well designed then their efficiency should be close to each other.
However the huge variable is the one you supply, the box their systems go into.
If you could get a box insulated as well as a good thermos bottle, then you could keep food cold, once it is already cold for very little power.

I have the new 40 qt plastic Engel.
It’s set at -5f, which is max cold, my boat interior furniture is 75f, the exterior of the Engel is 65f except when I move the trash can that is sitting on top of it, under the trash can it’s 55f. All temps with an IR thermometer that I have no idea how accurate that thing is, but I think it’s close.

[Typhoon]

I have a FLIR thermal imaging camera and use it every day . Those small power coolers are always the coldest thing in a cabin . So I would think that your digital laser thermometer is pretty accurate .

Regards John

[Copacabana]

Not to hijack the thread (I should probably start a new one...), but I have a question about adding insulation and would like to take advantage of Richard's and John's knowledge as they are posting in this thread. As I mentioned, I have the Engel 40-qt drop-in model. I don't think they made this model anymore. It's not a portable Englel. It's made to be mounted under a countertop (you cut a hole and it hangs from the edge around the hole). It has a plastic liner (inside the box) and a stainless steel outside shell (with the compressor mounted underneath the unit). It works great, but the outside of the SS box is always cold to the touch (so not so efficient). I have lots of free space around the box on all sides (perhaps 5 inches/ 12 cm). I'd like to improve the insulation on the 4 vertical sides. The bottom can't be improved as the compressor is attached to the bottom of the unit and there is no room to add insulation. Any suggestions? Also, I'm in Brazil and the options for insulation material are limited (I've never seen those 3M foam boards here). Thanks in advance!