ice box ?

[Bob Noodat]

Very interesting Bob! I hadn't seen a cooler box like that, but it works on the same principle as a swamp cooler, like the ones they used to make for cars.



Ah yes, the "latent heat of evaporation" rides again!

Thanks for those links above too, I'm researching this same topic, as we want to add some kind of refridgeration to our A-27 as well. I'm also considering an LP/electric unit, but in that case the fridge would have to be mounted in the cockpit where it could be vented overboard. We have a Dometic unit of that type in our old Avion travel trailer, and I am amazed by how little gas is required to keep the beer cold and the ice in our gin and tonics.

Tom

Neat picture, Tom.

The real problem with the RV absorption unit running on LPG would be getting air flow through the rear of the unit. RVs as you know have one or two big grills and can rely on passive flow. You'd have to have a 12V fan I think. Then you'd get into power usage problems again.

[sailonset]

A hot topic!
Looking again at that 40qt Dometic, it specs 5.5a, whereas the Engle is 3.0a. Big difference if meaningful. It does have a low-voltage shutoff, which is a good safety feature for the house battery bank. The Engel doesn't. The digital panel looks impressive, but once the dial on the Engel is set, the temperature is consistent.

I'm planning to power ours from the solar MPPT controller's output circuit, which features an LVD. Tomorrow March Hare will be in our side yard, so no more 20-minute trips to Brownell's to look, measure, poke and photograph.

[ssrig]

Propane isn’t really recommended for boats in general although there are many that have it, it is amazing the power of propane when it fills the bilge and explodes,, seen it first hand!
Absorption fridges suck in 12 volt mode, the element is on full time and will deplete a battery bank in no time and unless things have changed with the thermoelectric units, they can’t cool like a compressor fridge especially when the outside temps are up there and they too draw constant power and will drain batteries fast, had one on a sailboat and it didn’t work for me, been there done that.
A compressor fridge is really the best option for boats.

Power draw is a huge factor for these fridges, my expedition truck fridge that I have been running for ten years now is quite large with a substantial freezer and will make 4 trays of ice a night, I believe it’s 6.8 cubic feet? And while it is on will draw 5.2 amps with a duty cycle that is pretty high, like 45 to 50 minutes an hour and will pull somewhere around 80 amp hours in non daylight hours where the solar is not generating any power. It is a Nova Cool fridge with a danfoss compressor.
It is an upright fridge freezer so when the doors are opened to get a beer all my hard earned cold air flows on out of it so it has to make more which sucks!
Soooo, the chest fridges are much more efficient.

While researching for my boat fridge I looked long and hard at what is available and went with the Dometic Cfx models for several reasons, first is the unbelievably low power draw! I’m sure there might be a lower draw fridge out there but I never found it, Dometic stated an absurd 1.3 ah/h draw! And I believe it is close to that and the duty cycle is somewhere in the 30-45 minute range, very efficient! This is while making 4 trays of ice a day.

Price! 1,200 bucks as opposed to too much for Engels.

Lightest weight of the ones I looked at in that size range, I take ours out myself and keep it in our house for the winter.

Tops open individually for the fridge or freezer and each compartment has a light that comes on.

Each compartment can be independently controlled so they can both be fridges or freezers or conventional fridge and freezer set up.

So if anyone is looking for a fridge have a look at those, I think Dometic is creeping into the lead with these fridges but also time will tell. Oh, this is where I also state that I don’t work for Dometic and kind of feel they are taking over the RV world but dammit! This fridge sure is impressive and sure do like it.

Sorry to the OP as I saw after I posted that he has a A27 and not a A25 and isn’t asking about any types of fridges but I just had to get my 2 in.

[ssrig]

A hot topic!
Looking again at that 40qt Dometic, it specs 5.5a, whereas the Engle is 3.0a. Big difference if meaningful. It does have a low-voltage shutoff, which is a good safety feature for the house battery bank. The Engel doesn't. The digital panel looks impressive, but once the dial on the Engel is set, the temperature is consistent.

I'm planning to power ours from the solar MPPT controller's output circuit, which features an LVD. Tomorrow March Hare will be in our side yard, so no more 20-minute trips to Brownell's to look, measure, poke and photograph.

Most compressor fridges have low voltage shut off but they are to preserve the fridge not the batteries, typically pretty low voltage like 11 to 12 where a regular battery will be toast anyway.

Not sure I understand powering a fridge using a load side of an mppt controller, so only use the fridge during solar generating hours? Can you explain.

[sailonset]

The Victron 100/20 output isn’t the battery charging port. It draws from the battery like other devices. Useful for a 24-hour circuit.

[ssrig]

The Victron 100/20 output isn’t the battery charging port. It draws from the battery like other devices. Useful for a 24-hour circuit.

Ok, so you will use it as a battery disconnect in case of low voltage from the batteries, sorry, I had in my mind something different with the load coming from only excess solar power and not drawing from the batteries.

[Bob Noodat]

Thanjs for the lead on the Dometic, ssrib, great explanation and those characteristics seem to make it a real winner. I have in the past done a lot of cursing at Dometic though, for their absorption fridges......