50 degree ambient drop?

[Paul B.]

We're setting up an old FWC with batteries, solar, Engel or ARB, etc. We mostly run to Death Valley, Saline Valley.

Will these setups keep food and drinks COLD when it's 115 degrees in the day and 85 degrees at night?

Hence the thread title question. Is a 50 degree ambient drop all I should reasonably expect?

 

[unseenone]

I'm running mine with a 100 degree ambient difference with similar temps. Temp set to 0F.

 

[moabian]

My ARB lives in the Jeep year-round and has no problem maintaining below-freezing temps (around 20F) when it's over 100 degrees outside and significantly hotter in an enclosed Jeep. I run dual Odyssey batteries.

 

[Paul B.]

Cool! I'm getting ready to pony up some serious $$$ to put it together. Had read that even Engel doesn't guarantee more than 50 degrees.

I believe I'm leaning towards the ARB, seems the controls are more flexible.

 

[228B]

.

Is a 50 degree ambient drop all I should reasonably expect?

.
You may be thinking of the questionable performance of a Peltier-chip cooler. Imho, those things are an utter waste of time, money and battery amperage: at least a 5-amp draw and that is constant! And from what I've heard, yes; one can only really expect a 40 or 50-degree drop from ambient, and then only if what you put into the cooler is pre-chilled.
.
With your planned ARB or Engel, you have a TRUE refrigerator; a device with a (swing-)motor, compressor, Freon, etc. and one that draws nearly 50% LESS amperage and that has a considerably shorter duty cycle. Granted, it may run longer per hour (duty cycle) in 115-degree heat, but you can also add insulation in many forms. Just keep the refrigeration plant vent grid unobstructed.
.
With a healthy battery (in both capacity and condition or a dual-battery setup like moabian's), a good solar setup you may expect to able to use an ARB as a freezer in 115-degree heat if you wanted to. I have an Engel MT-45 purchased six years ago and it's going strong! I use mine as a reefer, usually. I purchased an analog food storage thermometer to monitor a 35-40-degree F. internal temperature. Newer units feature digital temp readouts.
.

 

[andytruck]

ARB literature does say a 50 degree drop from ambient temps. I am new so have not tried mine in excessive heat, but sounds like many of you are able to get a drop of more than 80 degrees (from 115 outside to freezing in the cooler)?

 

[Bbasso]

while my Engel MT45 never sees extreme duty like what you have planned, it can easily keep any temp I want...

 

[Ducky's Dad]

My Indel B 50-ish has held -21C/-6F in ambient temps as high as 128F (around Dateland AZ, 8/31/15). Fridge was full, truck had been driven for about 6 hours before we got there. Ice cream still hard the next morning (and afternoon). Your expectations are not unreasonable.

 

[andytruck]

.

.
You may be thinking of the questionable performance of a Peltier-chip cooler. Imho, those things are an utter waste of time, money and battery amperage: at least a 5-amp draw and that is constant! And from what I've heard, yes; one can only really expect a 40 or 50-degree drop from ambient, and then only if what you put into the cooler is pre-chilled.
.

They do have their place. They are cheap and for short trips do good enough. I had one all last year. I hated it when I tried to park for more than 3 days, but when I would drive, then stop for just a day or two it was fine as I had two deep batteries, and 100w of solar and often in summer sunshine. It did require all the electricity I could muster. The 100 watt solar was just not enough to keep up with the 4 amp constant draw, event adding two 100 watt panels I was on the losing side (but by then it was Fall and I was further north). They are for overnight trips only, otherwise dead batteries are likely, but cost effective if overnight is all you do, or just driving to the next power outlet.

Duckys Dad, does your fridge say 50 degree drop like the ARB states? Your story sounds like you started from the house with frozen contents, drove 6 hours and your stuff was still frozen??? A regular cooler will do that, but did yours keep it frozen for days of 128 degree high temps?

 

[Ducky's Dad]

A regular cooler will do that, but did yours keep it frozen for days of 128 degree high temps?

I lived with regular coolers for years, and they won't do that. I have rotomolded coolers, and they won't do that. We were out for five days on that trip, with maybe two hours of driving each day. Temps dropped from 128F to around 115F. Nights felt like they were in the low 90's. Stuff that we did not consume was still frozen at the end of the trip. Truck fridge is running on a pair of Optima Grp 34 Marine Dual Purpose batteries with a 270 amp alternator. Fridge is in the back seat, wrapped in a transit bag (old Waeco), and we usually throw more stuff on top for insulation.

I don't recall anything in the Indel manual about a 50 degree differential.