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DC Refrigerator
I followed in the footsteps of LATLJUS and installed a DC frig. It's a Norcold N8DC and is designed to replace our Dometics. It juuuuuuust fits depth-wise and is a little narrower and shorter than the Dometic. It screws in from the sides just like the Dometic and I added one screw on the bottom back. I added 1 1/4" trim around the front.

Sitting in my driveway, it's working great. On the middle setting, it keeps the freezer right about zero and the frig about 40. This is with outside temps in the 80s and low 90s. So far I am very pleased with its energy consumption. Of course, we're not opening it as we would while traveling but so far so good. We're going to take off on a trip in a week or two so I'll get some real use data but for now, so far so good.

I got the 8 cu ft Norcold but I believe their 10 will also fit.

The photo with the arrow shows the built in exterior latch.
jor
09 27' MB
10  Suby Forester

Re: DC Refrigerator
Reply #1
Looks great!

Was there space to upgrade the insulation?

Looking forward to hearing about the real world energy usage as I’d love to remove my factory fridge and use up a bit more of my 400ah of Lithium. capacity.
Dave

2017 TK

Re: DC Refrigerator
Reply #2
The extra 2 cu/ft of the N8DC's 8 cu/ft interior is a big improvement over the Dometic 6 cu/ft capacity. This is almost 60 extra quarts, a lot more than the 40 qt electric ice chest we carry. The next time the refrigerator dies, an electric model may replace it, depending on the power usage and if our LS's smaller electrical system can handle it without adding more solar, our roof is almost filled.
Checking Norcold's site,  the 10cu/ft N10DC refrigerator is 6" taller than the N8DC and will not fit most LDs, even with modifications.

Larry



Larry
2003 23.5' Front Lounge, since new.  Previously 1983 22' Front Lounge.
Tow vehicles  2020 Jeep Wrangler Rubicon, 2001 Jeep Cherokee
Photo Collection: Lazy Daze

Re: DC Refrigerator
Reply #3
Quote
Was there space to upgrade the insulation?

Dave, there is room on the outside wall for 1" of insulation. The first photo in my original post shows what I did. I also covered the vent door with Reflectix. There really isn't enough room on the sides but then the sides are inside the rig!

Quote
the 10cu/ft N10DC refrigerator is 6" taller than the N8DC

Larry, Right you are. The frig itself would fit but there's only 4" or so available above the control unit for the 8' model.
jor
09 27' MB
10  Suby Forester

Re: DC Refrigerator
Reply #4
These still generate heat.  Is that still vented out the top?  Is there vent/airflow under these units like home ones?   I ask since the exterior door is now blocked.
2000 Mid-Bath
2012 Lance 830 Truck Camper/2006 Cummins Dodge Ram Megacab
1985 Multi Plan - Donated to the American Breast Cancer Foundation.

Re: DC Refrigerator
Reply #5
I am considering the Vitrifrigo AC/DC fridge below.  Wondering if this model would fit width wise in the existing Dometic refrigerator space.  The height and depth appear to be OK.  Please provide me feedback.  Thank you!

Dimensions & Specifications of Vitrifrigo DP2600IBD4-F-2:
Total volume (Cu. Ft.)
8.1
Freezer volume (Cu. Ft.)
2.1
Net weight (Lbs.)
136.7
Power supply
12/24Vdc - 100-240Vac 50/60Hz
Nominal consumption
65 W (5.38A) - 12Vdc / 65 W (0.76A) - 115Vac
Overall width (In.)
24 13/16
Overall height (In.)
53 5/16
Overall depth (In.)
23 11/16
Panel color
black

2021 27MB 
Towing 2021 Ford Escape Hybrid AWD

Re: DC Refrigerator
Reply #6
JOR, I think you are still going to need some air flow on the back of your frig. That little fan has to exhaust and make up some air from somewhere.

Jon
1994 MB

Re: DC Refrigerator
Reply #7
Quote
Is that still vented out the top?  Is there vent/airflow under these units like home ones?
Quote
I think you are still going to need some air flow on the back of your frig.

I think I'm good for air flow. Lots of room on top. The frig has leveling legs and it sits an inch or so above the floor. The back of the frig has stoppers (they call them breaks) which provide space between my insulation and the tubing on the back of the frig. If you put your hand under the frig compartment you can feel the air blowing by.

I no longer have the top vent as I removed it for my solar installation. I sealed it with a piece of aluminum and installed a combiner box over it for the solar wiring (4 awg).
jor
09 27' MB
10  Suby Forester

Re: DC Refrigerator
Reply #8
Hi Jor;  Jon and Ramon have pointed out this problem.  A refrigerator/freezer is just a heat pump that 'pumps' heat energy from one place to another.  In this case from your food compartments to the air outside the box, and it needs to go somewhere.    When you said that you had covered over the roof vent, I assumed that you would have installed a side vent near the roof (outlet), and of course kept the airflow lower side vent (inlet) intact.  Many trailers and motorhomes with slide-outs do this also.

            The owners Manual:  https://norcold.com/wp-content/uploads/_pda/2019/07/OM_N8DCX_N10DCX-10_640137F_20230109.pdf  and an excerpt of page 7: "Refrigerator Care Checklist", at the bottom:
       "- Make sure the air flow in the lower intake vent, through the refrigerator condenser and coils and out the upper exhaust vent is not blocked or decreased.  ".

      So you will (void the warrantee) unless you restore that side vent, and the upper vent also, to get that heat away from the motorhome.
   RonB
RonB (Bostick) living in San Diego
Original owner of "Bluebelle" a '99 TKB

Re: DC Refrigerator
Reply #9
So you will need to restore that side vent, and that upper vent also, to get that heat away from the motorhome.
[/quote

Not necessary, the refrigerator can vent its hot air into the interior, the same as our home refrigerators. It can be set up to vent to the outside too. Since Jor has sealed the exterior access panel as well as covered the roof vent, he is committed to the interior venting now. His refrigerator is reported to be working fine with good interior temp in warm weather, it wouldn't do so if the condenser's waste heat was not removed through venting.

Larry
Larry
2003 23.5' Front Lounge, since new.  Previously 1983 22' Front Lounge.
Tow vehicles  2020 Jeep Wrangler Rubicon, 2001 Jeep Cherokee
Photo Collection: Lazy Daze

Re: DC Refrigerator
Reply #10

Not necessary, the refrigerator can vent its hot air into the interior, the same as our home refrigerators. It can be set up to vent to the outside too.

A system that could do both (adjustable, summer/winter) seems like a good idea to me. 

Rich
2003 MB

Re: DC Refrigerator
Reply #11
I'm going with Larry on this one. Like I said, there is plenty of air circulation going on. The top and side vents are sure necessary for the gas frig but not for the compressor frig in my opinion as it vents to the entire interior of the coach. I know many class A owners that have installed residentials and most plugged up both of those holes.

It's late in the year now so we're only in the 80s but when summer rolls around again, if the frig is putting too much heat into the coach, I'll restore the side vent. We'll see!!!  :D 
jor
09 27' MB
10  Suby Forester


Re: DC Refrigerator
Reply #13
Good info on 12 volt Refrigerators.
12-Volt RV Refrigerators Truths - Let's RV

Interesting read and possibly explains why so many newer rigs have 12-volt refrigerators.
The power usage test shows why a robust solar and battery system is needed to use a 12-volt refrigerator. With 75-100-amp/hours of power needed daily for the refrigerator plus the other electrical drains from daily living, this will require a full roof of solar panels, more batteries plus not minding always being parked in the sun. Could be fun in the summer.

For long-term boondocking, propane still seems to have an advantage, especially when winter camping or parked in the shade.
A full tank of propane can run the refrigerator for a long time and is a lot less expensive than the mega solar and battery upgrade needed for a 12-volt refrigerator.
More efficient electric refrigerators that use less power are needed. Electrics have been used on boats for years, often with custom-built lockers with the cooling unit remotely mounted. The mechanical parts being separate results in heat transfer into the locker. The locker walls can be many inches thick of high-R foam, instead of the inch or so of foam in RV gas or electric refrigerators. If interested in building your own, before is one of the many available 12-volt cooling units.
DOMETIC CoolMatic Cooling Conversion Kit | West Marine

Manufacturers and RV builders can do better to make electric refrigerators less power-consuming.

Larry


Larry
2003 23.5' Front Lounge, since new.  Previously 1983 22' Front Lounge.
Tow vehicles  2020 Jeep Wrangler Rubicon, 2001 Jeep Cherokee
Photo Collection: Lazy Daze

Re: DC Refrigerator
Reply #14
OP here. I took Larry's suggestion and installed a dedicated meter on the DC frig. I have a Victron 712 already but this little unit will separate the frig's power consumption from the rest of the coach. I installed it right next to one of the batteries. Just open the compartment and see what's up. The wiring is a little funky but I'll probably remove it once I have a handle on the current draw of the frig. I am really looking forward to seeing how this does on the road. Hopefully, we'll get out of here in a week or so. Just gotta figure out where we're going!  :D
jor
09 27' MB
10  Suby Forester

Re: DC Refrigerator
Reply #15
I think I'm good for air flow. Lots of room on top. The frig has leveling legs and it sits an inch or so above the floor. The back of the frig has stoppers (they call them breaks) which provide space between my insulation and the tubing on the back of the frig. If you put your hand under the frig compartment you can feel the air blowing by.


Ok, thanks for the update.. I looks like you put trim around the entire perimeter to close gaps and it is hard to tell on top if there is a gap for hot air to escape in front of the fridge and to the living area or not, which is why I asked.   My home fridge is huge and in a tight spot...  in the summer it does not cool as well as now, meaning It runs more than I like in the summer...  should have bought a smaller unit but there are 5 of us.  I would need to raise a cabinet above it or pull it out more but that creates other problems.  Coils are clean as that wreaks havoc as well.   Please keep us posted. 
2000 Mid-Bath
2012 Lance 830 Truck Camper/2006 Cummins Dodge Ram Megacab
1985 Multi Plan - Donated to the American Breast Cancer Foundation.

 
Re: DC Refrigerator
Reply #16
I have researched these and have one planned for our new RV, though I am looking at a different brand (though similar).

Venting happens under the refrigerator, out to the front of the fridge.

Usage is roughly 5 amps an hour - potentially less depending how much it is opened and temps (inside and outside).

There are units that have two compressors
- one for the freezer and one for the fridge, potentially 4-5 amps but if the freezer is opened a lot less the amps on that can be lower.
The one compressor units work similar to absorption in that the fridge temp is tied into the freezer one (eg x degrees less).
With two separate compressors you can set the temperature for each compartment (freezer, fridge) separately.

Bigger solar/battery is needed for boondocking, especially if you are also adding mini split(s) - heat pumps that do cold air conditioning and heating, and/or Starlink.

Jane & Scott
Currently have a 1989 TK  LD we did a lot of upgrades on.
Bigfoot 25RQ Twin on order with early summer 2024 ETA

Our smartphone autocorrects into very poor English.
 We disclaim the illusion of ignorance this creates as we have enough ignorance we rightly claim.

Re: DC Refrigerator
Reply #17
Quote
With two separate compressors you can set the temperature for each compartment (freezer, fridge) separately.

I don't know how it's accomplished but the single compressor Norcold allows for setting separate temps.
jor
09 27' MB
10  Suby Forester

Re: DC Refrigerator
Reply #18
The one compressor units work similar to absorption in that the fridge temp is tied into the freezer one (eg x degrees less).
With two separate compressors you can set the temperature for each compartment (freezer, fridge) separately.

This seems unlikely - as with a home fridge where valving is used to adjust fridge/freezer differential, I imagine that is the case with RV compressor models. Absorption fridges don't have that as a viable option. Dual compressors would only be used in situations where the fridge is accessed frequently - such as a restaurant. Hard to believe one designed for low energy consumption as in an RV would use this solution.

Steve
2004 FL
2013 Honda Fit

Re: DC Refrigerator
Reply #19
Dual compressors would only be used in situations where the fridge is accessed frequently - such as a restaurant. Hard to believe one designed for low energy consumption as in an RV would use this solution.

After searching, I found that none of the available electric refrigerators that fit our LDs have dual compressors.
Steve has it right, the refrigerant is controlled by valves that direct the refrigerant to the needed compartment's evaporator.
I would like to see a link to a refrigerator that does have dual compressors and will fit in an LD's refrigerator opening.

Larry
Larry
2003 23.5' Front Lounge, since new.  Previously 1983 22' Front Lounge.
Tow vehicles  2020 Jeep Wrangler Rubicon, 2001 Jeep Cherokee
Photo Collection: Lazy Daze

Re: DC Refrigerator
Reply #20
I would suspect that the dual controls on JORs frig is a lot like our house hold frig. There is a temp control ( thermostat) that controls temp then the second control is a damper that redirects air from the freezer to the cooler section. I dought that dometic or whoever would go to the expense of solenoid valves but maybe.

Jon
1994 MB

Re: DC Refrigerator
Reply #21
Check out Nova Kool Manufacturing ULC
Canadian, part of novacold company.

Info on temps being tied together come from the technical support at the company.

A side FYI, Dometic 12v users report many more problems than novakool.
Jane & Scott
Currently have a 1989 TK  LD we did a lot of upgrades on.
Bigfoot 25RQ Twin on order with early summer 2024 ETA

Our smartphone autocorrects into very poor English.
 We disclaim the illusion of ignorance this creates as we have enough ignorance we rightly claim.

DC Frig Energy Use
Reply #22
OP here. I've been tracking the frig energy consumption for several days now. I have Larry's recommended measuring device dedicated to the frig. We're about ready to take off so both the freezer and frig are loaded. After filling the freezer I had to turn the freezer control to the maximum position (5). I have the big compartment on 3 or 4. The freezer is maintaining 2 to 3 degrees and the frig about 38 (1 to 5 with 5 being coldest).

So far, after three days measuring at the same time each morning, the new frig is consuming right about 600 watt hours in a 24 hour period. That's just about 50% of one of my three 100 ah lithiums (1280wh). Of course, this is a driveway measurement. Once we get going, I'll keep taking daily measurements and should have a realistic energy usage report.

This Norcold has a "night" mode which is supposed to be more efficient. You press the button and it goes into night mode for 8 hours. Not sure exactly how this works and I have not been using it thus far.

I'm just using solar now and the batteries jump right back to 100% but of course, we're in the Arizona sun country. We'll see how it goes. I have the DC to DC charger and of course, the generator as backup.
jor
09 27' MB
10  Suby Forester

Re: DC Refrigerator
Reply #23

I may have mentioned this before, but I've found Govee's inexpensive wireless temperature/humidity sensors (twelve bucks on Amazon at the moment) extremely useful for tracking fridge/freezer performance. That's thanks to the well-designed Govee smartphone app, which in addition to showing current readings, can display historical data as a graph. You can also set alarm points for both low and high temperatures.

I have five of these little modules in use, monitoring temperatures in my rig's fridge, freeze , interior, and exterior, as well as in my truck's fridge. The Govee app provides a quick overview of all five, as well as detailed historical data on each.

(Govee recommends against using these in a refrigerator or freezer, but I've been using them that way for years with no problems.)

As an Amazon Associate Lazy Daze Owners' Group earns from qualifying purchases.
Andy Baird
2021 Ford Ranger towing 2019 Airstream 19CB
Previously: 1985 LD Twin/King "Gertie"; 2003 LD Midbath "Skylark"

Re: DC Refrigerator
Reply #24
Jane (and Scott) mentioned NovaKool. And they do have a dual compressor model refrigerator that at 6.8 cubic feet total will fit in our coaches.  The RFU6406 D is 46 1/2" tall. My Dometic is over 52" tall.  The NovaKool is 20 1/4" wide and the Dometic is 24" wide.  The depth is 19 3/4" deep. I didn't measure that but it should be less deep than the Dometic.  Freezer is on the bottom.    At 12. volts the current draw is 4.2A each compressor. I would hope that the two combined, after factoring in run time, would be about the same overall power as a one compressor box.
   added on to original post:  the RFU 8250 at 7.3 cubic feet is an even closer match to my Dometic Royale 'fridge (Lazy Daze original)  at 52 7/8" x 23 1/4" x 19 1/2".  So you get 1.3 cubic feet more storage. Pull out freezer drawer on the bottom so you don't lose as much cold air when open. Possibly you could run both compartments as refrigerators or both as freezers. Maybe a little double redundancy if one were to suddenly fail (medications?).
    I would probably go with the single compressor model. Then I could preload it in my angled driveway, and I could leave it running after returning from a trip, instead of having to unload it immediately like I have been doing for the last 35 years. I would add another Li battery (or two) for 600 AH, or 800 AH (10.4 kwh total 4 batteries).
    Larry, you could dispense with the extra cooler and get the space between seats back.

https://static1.squarespace.com/static/5f3bfb120aae2d0e9e21afe5/t/64c98a17e8660221b0119037/1690929687743/Spec+Sheet+ImperialMetricLT+2023+-+R5.pdf                    RonB
RonB (Bostick) living in San Diego
Original owner of "Bluebelle" a '99 TKB