Converting from a 2-way fridge to a 3-way fridge

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Technically you have a three way,,,,,,with the advent of INVERTERS, you seldom see three ways anymore.. With the inverter you can run the fridge on (1)120 (power pole)  (2) LP which it has...and (3) 12 volts thru the inverter... Way cheaper than the money to convert.>>>Dan
 
Petey/59 said:
Can I convert from a 2-way Norcold DE-0061/EV-0061 fridge to a 3-way fridge?


Welcome to the forum. Others will offer their opinions on this. I have deleted your other two duplicate posts, it is not necessary to post a topic more than once
 
Petey/59:


Yeah, there is no need for a 3 way fridge.  Running it on 12V takes SO MUCH power that your batteries will be depleted in short order.  Propane is a much better idea when you don't have shore power.


About the only time you can't use propane is if you are on a ferry somewhere, or are parking underground.  Then you are supposed to turn off the propane bottles at the tank valve, as propane is heavier than air and tends to 'pool' if there is any sort of leak.  However, if the fridge door is closed, it will stay cold for hours even if the fridge is turned off.


Frank.
 
I can't think of any practical way to do that, nor any good reason to try.  3-way fridges have a 3rd way to generate heat for the boiler, a 12v powered heater element. It would be in a pocket welded to the boiler, much like the 120v element is. Plus you would need switching on the controller to turn it on/off, and some way to select the new 3rd heating mode.

As others have mentioned, you can accomplish much the same end result by powering the 120vc mode with an inverter.
 
After reading the initial post, it isn't clear whether the poster is looking to change out the fridge or modify the existing one.

If replacing the fridge, yes it is advantageous to have the 12 volt heating element and option. It is great while u are traveling but isn't usually powerful enough to keep the fridge at operating temperature under normal use. Although the option is still available from fridge makers, rv makers have mostly stopped using the option as inverters have become common place in rv's but that is not indicative of the value of having the option.

Inverting 12 volt dc to power the 120 volt element uses a ton of 12 volts for the conversion. This is mostly because the 120 volt element is designed to run the fridge under normal use and anytime you convert from 12 volts to 120 there will be a factor of about 10 applied. The 12 volt elements were designed to maintain cabinet temperatures under little or no use of the fridge.

Adding a 12 volt element and circuit to an existing fridge is alot to ask for and probably isn't worth the effort. If you plan to replace the existing fridge then most certainly it is advantageous to have the 12 volt option and may only require a new 12 volt circuit to feed the 12 volt element.

I am a fan of the 12 volt option. My first coach had the option and I used it while the coach was rolling down the road. It worked wonderful. I also believe that that coach builders stopped using the option for economic reasons and not because it is not a good option.
 
Henry J Fate said:
After reading the initial post, it isn't clear whether the poster is looking to change out the fridge or modify the existing one.

I read the post and I thought that the OP has a 2 way Norcold and wants to make it a 3 way.  He said:

Can I convert from a 2-way Norcold DE-0061/EV-0061 fridge to a 3-way fridge

Maybe we need him to be more specific.
 
Inverting 12 volt dc to power the 120 volt element uses a ton of 12 volts for the conversion. This is mostly because the 120 volt element is designed to run the fridge under normal use and anytime you convert from 12 volts to 120 there will be a factor of about 10 applied. The 12 volt elements were designed to maintain cabinet temperatures under little or no use of the fridge.
There is a conversion loss, Henry, but nowhere near the 10x you have implied.  In a modern electronic inverter, power conversion loss is on the order of 5%-8%.  Watts are watts, whether they are produced by AC or DC, and a 240 watt heater always uses 240 watts to produce the required heat.  To get that 240W of power directly from the battery requires 20A @ 12v, but it get it from the battery via an inverter requires about 21A @ 12v.    So, there is a cost to invert, but it's moderate.  Insignificant while driving, but noticeable when camping off-grid.  However, both the direct 12v and the inverter 12v are substantial loads when off-grid.  No free lunch here.
 
I agree Gary and I apologize for not being clear on my numbers.

The factor of 10 I use applies to amps for amps when inverting from 12vdc to 120vac. I use 10 because it's easy to estimate. It actually is more accurate at 11.

This means that an appliance needing 1 amp of 120vac will use approximately 10 amps of 12vdc when inverting. 11amps would be closer but a factor of 10  is an easy factor for rough calculations.
 
Petey/59 said:
Can I convert from a 2-way Norcold DE-0061/EV-0061 fridge to a 3-way fridge?

Welcome to The RV Forum!  Let's start over ...  ;)

The short answer is no, you can't convert THAT refrigerator to work on propane, but you can install a propane-electric refrigerator in it's place if you provide proper venting to the outside of the RV for the propane flame and the waste heat.

The Norcold DE-0061/EV-0061 is a compressor driven refrigerator that operates on 120 VAC or 12 volts DC.

Propane refrigerators use a completely different cooling process.  Instead of a compressor pressurizing Freon gas to create cooling, a heat source like a small flame or an electric heating element boils a water and ammonia mixture and the resulting gasses cool the refrigerator when they condense back into liquid form.

If it was me, I'd keep that refrigerator and install some additional batteries to extend the time before you have to start the generator and recharge them.  Or add some solar panels to charge the batteries and eliminate having to start the generator at all. 

A compressor driven fridge is much more energy efficient than a propane fridge, making it practical to run on battery and/or solar power.  It will continue cooling when it's off level and in 100+ degree temperatures, two cases where propane refrigerators come up short.

You can install enough solar capacity to run that refrigerator indefinitely for less cost than replacing the fridge.
 
We were having a good discussion about the 12 volt fridge option and then someone comes along and shuts the door on us :)
 
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