Refrigerator Question?

[Sportsman Matt]

Anyone have a Norcold 12V fridge mounted in their camper? Not talking the 3 way or portable cooler type units, but something on the lines of the DE-0041T. Reason I'm asking is I am working on a new truck camper build, and the info from Norcold doesn't say if it needs outside ventilation, unlike the propane models that call for exterior vents both top and bottom like my Norcold N300.

Other thing is how feasable is it to have the 12V over the propane unit? I know there is a price difference, but I know that I can go for 3 weeks on a 20 lb propane tank, but not sure about the 12V refrigerator running off 2 deep cycle batteries for a week of remote camping and fishing.

[kerry]

I doubt two batteries would power the frig for a day or maybe two without being recharged.

Here's an explanation of how much an Engel 12V frig draws:


If my vehicle’s engine is turned off, how long can I safely leave the Engel 12-Volt Refrigerator Freezer plugged into my cigarette lighter socket before compromising the battery’s ability to start the vehicle?
The safe answer here is approximately 3 hours in most situations. Actual conditions will vary depending upon the number of electrical devices that have been switched on during the last part of your drive (wipers, lights, blower, defogger, radio, cell phone, aux heater, cooler and or other accessories) and what driving conditions have just been experienced (high speed highway or stop and go traffic). Further limitations and factors are the relative condition of the battery and it’s charging system as well as season, temperature, and weather conditions.
Under ideal conditions your Engel 12-Volt Refrigerator Freezer could be run for many hours on just battery power. Under the worst combination of conditions, accessories could potentially deplete the battery in 10 to 20 minutes. Some vans have 10 or 12 bulbs lighted when the interior lights are on. Just these lights can drain a battery below starting power in about 15 minutes, without any other electrical device being present. Good judgment is required when making the decision about whether or not to leave any device plugged in while away from the vehicle. The best way to understand your situation is to test it before you count on it.

[FlatlinesUp]

DE-0041
specs show at 12vdc it draws between 2.8amps, call it 3 to be safe.

My two deepcell batteries have 125 amp hours for a total of 250

250/3= 83.3 hours till compleate drain, but you shouldn't drain past 60% very frequently, so 83.3 x .6 = 50 hours you can safely run it without recharge

put your two deepcells in parallel and isolate them from your starting battery and you don't have to worry.

Keep in mind if you want to deal w/24v that the norcold specs show 1.6amp draw.

[whatcharterboat]

Hey guys, a word on doing your calcs for power consumption of a fridge.

Sometimes a manufacturer will quote low power consuption by averaging out the consumption over a day. Sounds like it here. Most fridges run Danfoss compressors. Engel make their own. A Danfoss will draw about 4.7 amps at 12volts. The actual daily consumption is going to depend on the duty cycle and this will depend on how effective the insulation of the fridge cabinet is. Something to think about antyway. Hope it helps.

[whatcharterboat]

The actual daily consumption is going to depend on the duty cycle and this will depend on how effective the insulation of the fridge cabinet is.

And of course the ambient temperature.

[michaelgroves]

Most fridges run Danfoss compressors. Engel make their own.

I believe Engel use a Tecumseh compressor. We found the Engel seemed to run down our batteries noticeably more quickly than our home-made Danfoss-based freezer, and didn't perform as well either. As you say, it's all down to insulation (including positioning), venting, usage (keep it full, and closed!), and ambient temp.

I think the question of what other accessories are being used, and what was being used last time you ran the engine etc., is something of a red herring. Of course, if you have loads of lights and other stuff running at the same time, it will run your battery down more quickly, but to be useful, you have to factor those out of the equation to understand what you might be able to achieve with the fridge/freezer alone.

[fisher205]

I believe that Norcold is similar to my Nova Kool. I can last 3-4 days on two deepcell (27's ) batteries again it depends on how much other power I am using. I am pretty frugal with the power usage. The Nova Kool will shut itself down before batteries get low enough to do damage as I have found out. I believe the Norcold is similar. I looked at the Norcold but got a better price on the Nova Kool. THe manufacturer should have specs for how much air exhange they need. It doesn't have to be external venting like a gas refrigerator requires. - Brad

[whatcharterboat]

Hi Michael, How are you going? Good to talk again.
Interested in how much your 6 wheeler Landy weighs fully loaded? Telling my brother about it. He's a Defender Driver.

.

I believe Engel use a Tecumseh compressor. We found the Engel seemed to run down our batteries noticeably more quickly than our home-made Danfoss-based freezer, and didn't perform as well either. As you say, it's all down to insulation (including positioning), venting, usage (keep it full, and closed!), and ambient temp.

Not sure. Always thought they were there own. Don't know where I got that from. I used to do pipeline robotics. All my mini tractors had Engel planetry gearboxs. Excellent engineering. Also I fitted an Engel compressor / plate kit to a yacht a few years back. They made their own cabinet using 3" urethane foam with a tapered silicone seal. So the lid was like a plug with effectively a 3" thick seal as well. Then they put a light weight cutdown timber door over the top and that was the dining table. Very, very good performance with the better insulation.

The lines came pregassed. Or I should say one line . One of the lines ran inside the other to make it even easier to run them. The compressor came with a 240v /12v changeover too.

[VicHanson]

I've been trying to figure out some way to solve the refrigerator problem without using propane too. Just found this thread on the Sprinter forum, looks like it has a lot of information - there are 11 pages, haven't read them all yet.

http://sprinter-source.com/forum/showthread.php?t=5723

Vic

Hey, I'm an observer now!

[Sportsman Matt]

After havng several discussions over the phone with a couple techs in the RV business, along with more research by reading forums found on Google, I'm going to steer clear of the Norcold DC unit, and go with a Nova Kool. Similar price, but Norcolds it appears have compressor problems that develop within the first couple years and cost big bucks to have repaired, even under warranty.

Only thing is that you need to make sure is that the back of the unit has just enough space to create a tunnel for the air to be pulled in from underneath and through the coils in the back, and out the top of the unit, most Nova Kool info calls for a 30 sq inch vent top and bottom, and speaking to one tech, needs 1" behind the unit (which has already been designed in the cutout dimensions Nova Kool puts out with their spec sheet)

Now on to more designing nightmares, hopefully I'll get to the construction stage this spring.