Fridge/Freezers

BajaTaco

Swashbuckler
BTW, I notice that Engel has a new 80 litre model available now or very soon...

The MT80F

and I guess they will also make a unit with separate fridge and freezer compartments, the MT80F-C COMBI. Pretty cool! :cool: (pun intended) The MT80F-C is noted in their ad in the latest Australian 4WD Monthly mag, but looking at their site, it appears that maybe the split chest version actually only comes out to be 75 liters (which makes sense depending on the interior construction). Regardless, that is a sweet option!
 

RAM5500 CAMPERTHING

OG Portal Member #183
expeditionswest said:
I have two of the 45L models, and find them to be a bit snug for trips longer than 3-4 days. What makes it worse, it that I need to use two coleman jell ice packs to keep things cool through the night. I do not have the aux. battery system finished yet, so this is a requirement.

Will it drain the battery dead, just from leaving it running one night? Are you talking about fridge or freezer mode? I am in the market for one of these and want to make sure i have all my details in order. From all my previoes "Net Research" they should be able to be run for 2-3 days and the battery should have plenty of power to start the rig. Am i wrong? Need to find out soon, i planned on getting one of these for my 5 day, self sufficent trip to Baja for new years. If i need an AUX battery to get it to work, i might have to rethink things.


Also, how long can these things be run continuous? Any ideas? You guys plan on running these none stop on the cabo trip?

Input?
 
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RAM5500 CAMPERTHING

OG Portal Member #183
blupaddler said:
Yeah, that is kinda pricey. But the stainless steel is a good option for the marine environment.

There is also a guy on craigslist, in the LA area, selling two Norcold 40's for $500 each. Maybe someone can bargain with him.

Hey Rob

Are you in the market for one? I might be interested in doing this with ya. Lets go offer him $900! :D

What condition are they in? I am free this weekend for the drive!
 

BajaTaco

Swashbuckler
BM, I definitely wouldn't risk running one for 2-3 days on a battery that is used for starting and running the vehicle. There are too many variables involved. If you want to take a fridge on your Baja trip and don't have time to set up an aux. battery, just borrow or buy one of those portable jumper battery packs with a decent reserve on it, and use that. You can recharge it while you drive by connecting it to a cigarette lighter outlet. Or you could just take a 12VDC deep cycle battery for that matter, if you have a safe place to secure it. You can charge it via the 12V outlet plug as well. Just rig up a paired wire with a cig. lighter adapter on one end, and a pair of alligator clips on the other.

I did a little voltage test with my 60 liter one hot weekend in the desert - I'll dig up the info. Also - take a look at the thread here on solar power for Scott's truck. We did some estimates on fridge power consumption there I think.
 

RAM5500 CAMPERTHING

OG Portal Member #183
BajaTaco said:
BM, I definitely wouldn't risk running one for 2-3 days on a battery that is used for starting and running the vehicle. There are too many variables involved. If you want to take a fridge on your Baja trip and don't have time to set up an aux. battery, just borrow or buy one of those portable jumper battery packs with a decent reserve on it, and use that. You can recharge it while you drive by connecting it to a cigarette lighter outlet. Or you could just take a 12VDC deep cycle battery for that matter, if you have a safe place to secure it. You can charge it via the 12V outlet plug as well. Just rig up a paired wire with a cig. lighter adapter on one end, and a pair of alligator clips on the other.

I did a little voltage test with my 60 liter one hot weekend in the desert - I'll dig up the info. Also - take a look at the thread here on solar power for Scott's truck. We did some estimates on fridge power consumption there I think.

What about starting the rig every 8 hours or so and letting it run for a bit? :confused:

I will be with 4 or 5 other rigs that could "Jump" me if needed.

What do you think?
 

Scott Brady

Founder
It is completely dependent on ambient temps. I killed a yellow top optima in 14 hours in the Altar Desert. I was glad to have the little back-up battery unit to start the truck with.

Here are some measurements I took during the Expedition Trophy:

Measurements of voltage drop on blue top optima 55ah aux. battery.

Day one:
Ambient: start 78
starting voltage: 12.9v
ending voltage: 12.1v
hours of operation: 16 hours

Day two:
Ambient: start 62
starting voltage: 12.8v
ending voltage: 12.2v
hours of operation: 14 hours

Day three:
Ambient: start 58
starting voltage: 12.8v
ending voltage: 12.1v
hours of operation: 13 hours
Note: included running laptop for 2+ hours 75watts

Technically, if the fridge ran non-stop, you would reach an optima blue top depth of draw at 10.8 hours.

Engel 45l: Amp Draw: 2.5
Optima at 50% DOD: 27 amps

27/2.5= 10.8 hours

Depth of draw is critical for evaluating battery requirements and accessory impact on amp storage.
 

BajaTaco

Swashbuckler
Boston Mangler said:
What about starting the rig every 8 hours or so and letting it run for a bit? :confused:

I will be with 4 or 5 other rigs that could "Jump" me if needed.

What do you think?

I think that would be a waste of fuel and add unnecessary pollution to the beautiful skies of Baja ;) If you let the fridge flatten the battery, you will just reduce the life of the battery. If it's a deep cycle, it won't eat into the life cycle as much. If it's a starting battery, you will do some pretty good damage to it by letting it run flat.


Scott, the ambient temp that you cited in your record - is that outside ambient air temp? If so, what time of day is the recorded run-time happening? Was the fridge on the whole time for each run time cited? What temp. were you maintaining inside the fridge, and what was the temp inside the truck cabin during the run time?

"Technically, if the fridge ran non-stop, you would reach an optima blue top depth of draw at 10.8 hours.

Engel 45l: Amp Draw: 2.5
Optima at 50% DOD: 27 amps

27/2.5= 10.8 hours"

When you say 27 amps, you mean amp-hour capacity, correct? The fridge doesn't run non-stop, it cycles on and off as conditions dictate to maintain the temperature setting via thermostat control, so I think the 10.8 hours could be potentially doubled or quadrupled or even more depending on variables such as ambient temps, contents of fridge, lid-opening frequency, humidity, etc.


BTW, I found my notes for that one little test I did at KOFA. This was during a pretty warm time of the year, and I did a little expiriment using some ice containers in my fridge to supplement the cooling and reduce run time. Keep in mind that I maintained a temperature a bit above what I normally run, which is 28-32 degrees F.

To quote myself:

" This past weekend, I went to the Kofa Nat'l Wildlife Refuge to train with Scott and Uwe for the adventure race. I tried an obvious trick with my fridge - I used two plastic containers of water totaling 3.5 gallons, and froze them before I left on the trip. I loaded them in the fridge with my food and drinks and left on Friday afternoon. I got to camp around 7 pm on Friday night. The truck stayed parked until Sunday around noon (about 41 hours). I adjusted the thermostat on the way to Kofa so that the fridge would maintain about 33° F (0.5° C). At camp on the first night, I adjusted it to about 36° F (2.2° C). Before retiring for the night, I turned it off. I was careless and did not record the overnight ambient air temperature in the cabin where the fridge is (in fact, I neglected to record actual cabin temps all weekend - my mind was preoccupied with other things). My guess is that overnight temps were in the low 60's F (mid teens C). When I checked the fridge temp. in the morning, it had only increased by 2 degrees. We left for the day's training, and I had to lock up the truck. I left the side vent windows cracked open for some air circulation. I adjusted the thermostat to the highest temperature setting to drain the battery as little as possible. I am sure the ambient temperature inside the cabin exceeded 100° F (38° C) during midday on both days, as outside temps were likely in the mid 90's F (mid 30's C). I checked the fridge on late Saturday afternoon when we returned, and it was at a cool 40.7° F (4.8° C). Not bad! I again turned it back down to a setting of about 36° F (2.2° C) for the rest of the evening. Once again, I turned it off before retiring. Sunday was a repeat of the previous day, except that we departed camp around noon. Before leaving, I pulled the negative connections from the battery and let it sit for about 15 minutes before taking a voltage reading with the MM. I recorded a voltage of 12.7 volts. Keep in mind that other than the fridge, I only used the battery for about 20 minutes of VHF radio operation, and maybe 10 minutes for a 5W halogen lamp.

Using this info, I can see an advantage to having a 60 liter fridge is the ability to put some nice big ice containers in there to reduce power consumption, and still have ample room for food and beverages. Of course, this ratio would diminish on a longer trip, but it is still pretty nice. Also, adding some insulation to the box for the time when it is sitting idle in the heat would certainly help as well. I noted that one of my ice containers (2.5 gallon), did not have a chance to freeze completely before I removed it from the freezer at home and left for the trip. The one gallon container did. If I was able to get the larger container to freeze solid, that would have helped even more. Using this preliminary data, I am speculating that I could use about 35-40% (24 liters) of the storage capacity for ice containers, and use the remaining (36 liters) for food and drink, and be able to park the vehicle for possibly 4 days without flattening the battery (or running out of food?). Beverages can always be added to the fridge as needed (but this will increase power consumption somewhat). And this also depends on the type of beverage and ambient dry storage temperatures. I will just have to expiriment more! "

Needless to say, That was over a year and half ago, and I haven't really done any more recorded testing. :p
 

Scott Brady

Founder
BajaTaco said:
Scott, the ambient temp that you cited in your record - is that outside ambient air temp? If so, what time of day is the recorded run-time happening? Was the fridge on the whole time for each run time cited? What temp. were you maintaining inside the fridge, and what was the temp inside the truck cabin during the run time?

It was the outside air temp at the time I shut the engine off. I did not sample the outside air temp during the test cycles.

I do not know how often the fridge ran, or how long, just the voltage drop.

I was maintaining 28 degrees in the fridge.

BajaTaco said:
"Technically, if the fridge ran non-stop, you would reach an optima blue top depth of draw at 10.8 hours.

Engel 45l: Amp Draw: 2.5
Optima at 50% DOD: 27 amps

27/2.5= 10.8 hours"

When you say 27 amps, you mean amp-hour capacity, correct? The fridge doesn't run non-stop, it cycles on and off as conditions dictate to maintain the temperature setting via thermostat control, so I think the 10.8 hours could be potentially doubled or quadrupled or even more depending on variables such as ambient temps, contents of fridge, lid-opening frequency, humidity, etc.

It was an absolute calculation, showing worse case. I try to use this as the test of the systems ability to perform under the most brutal of conditions, like a week in the jungle, etc.

I have had times when the fridge ran non-stop. This is especially true when it is hot out, and Steph and I are drinking fluids. Opening and closing the fridge, putting warm drinks inside, etc. :sunny:

During my first trip into the gulf region in October of 2003, the fridge ran non-stop for 4 days. It was 114 degrees when we hit the rail tracks north of the salt flats.

I will say that the transit bag has made a big difference in the performance of the fridge. The sun cannot bake the top lid anymore, and the fridge holds temps much longer when not running.
 

BajaTaco

Swashbuckler
Ahhh, ok, thanks for answering my questions. ;) I mentioned the constant run-time just to clarify that the 10.8 hours isn't an absolute, but I can see using that for worst-case scenario. One more question - I noticed that on Day Two you started with more voltage than you ended with on Day One. So this wasn't starting the cycle in the morning, but rather in the evening? And your run-times were overnight (when it is cooler)? I am trying to remember that weekend, but my guess is that Day One cycle started in late morning (on Friday), and ran until the evening when we went to the river crossing. Day Two cycle would have started in the evening (at camp) and gone overnight to morning. Day Three cycle would be an evening cycle as well.
 

RAM5500 CAMPERTHING

OG Portal Member #183
BajaTaco said:
Pete, you could use solar alone to charge an aux. battery, but I think you would really be limiting the potential return on your battery investment quite a bit. By not connecting it to the vehicle's charging system, you will miss out on the opportunity (every time you drive the truck) for a relatively fast charging source to get your battery topped off. Chances are you won't have the solar hooked up while driving (unless you can do full-time roof panels) and even when you do have the solar hooked up, it will likely take hours to get a drained battery charged back up.

How big would you need to go for solar? I'm not sure, but my guess is probably 100w. Keep in mind that this depends on a lot of variables. From what I have seen, solar is very expensive and I'm not sure if the price tag lends itself to the typical budget for a compact expedition vehicle. I would be tempted to just buy an additional deep cycle battery, and only take it along on trips where you intend to be parked for more than 3 days.

To answer your last question, I am using a Norcold fridge (same as Engel/ARB).

Check this out:
http://www.fridgefreeze.com/recreation/prod-accessories.html
 

RAM5500 CAMPERTHING

OG Portal Member #183
Hey Guys

I just bought a 45qt Norcold and had a question. Do these things give off any kind of condensation at all?

I am planning on building a little box thing with the fridge on top and my power inverter underneath it seperated only by a piece of 1/2" plywood and about 2" of air. Anyone see a problem with water getting onto the inverter or are these things persperation free?

Thanks!
 

RAM5500 CAMPERTHING

OG Portal Member #183
BajaTaco said:
Congrats!!

Got it for $485 NEW plus $22 shipping!!!! It is the Norcold MRFT-40!

BajaTaco said:
I have had no issues with condensation on the outside of my unit.

Cool! Glad to hear it! I am on a mission to find that cool thermometer setup you have? :)

Also, does anyone have that Engel "Transit Lock" sliding thing? Not the big $ one metal, but the $65 one? Curious to see it in action!

Thanks
 
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BajaTaco

Swashbuckler
Boston Mangler said:
Cool! Glad to hear it! I am on a mission to find that cool thermometer setup you have? :)

I haven't seen any more specifically like the one I have, but any 12V thermometer with the little "outdoor" sensor should work fine. Or you could go all out and get a sweet LED digital Cyberdyne temp. gauge like the ExWest Taco has. Good find on the fridge deal. Man, you are gonna love it.

:jumping: :beer: :chowtime:
 

RAM5500 CAMPERTHING

OG Portal Member #183

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