Changing refrigerator cooling unit...New or Refurbished??

[SJ-Chris]

Summary: When replacing the cooling unit on your refrigerator, would you go with a refurbished unit ($450) or a new unit ($650)??

Here's the story...
I have a 2015 Thor Majestic 28a. The refrigerator is a Dometic DM2852RBX (8 cubic feet).

Recently it stopped cooling on either propane or electric. I tried all the troubleshooting things I could to no avail. The heating element is good (as I can feel the stack getting hot on either propane or electric).

So I took it to my RV repair shop. They diagnosed it saying the cooling unit was bad. They told me they recommend replacing the entire refrigerator (~$2200 for the new fridge which includes their 40% markup, plus ~$500 in labor).

I asked them how come they don't just replace the cooling unit. They said "they can't find parts for this particular unit". I spent 2 minutes googling and immediately found the parts (refurbished or new cooling units). I suspect replacing the entire refrigerator is a much higher profit for the repair shop which is why they recommended that (...thanks a lot, right??).

I've decided I'm going to fix it myself. I'm pretty handy. There are several youtube videos showing start to finish and it looks pretty straight forward. I pulled the refrigerator and layed it down on a blanket on my couch. Then I removed the existing cooling unit being careful to label everything and take lots of photos. It only took me 40 minutes to do so and it came out super clean which I was happy to see! I wanted to make sure I could remove it successfully without damaging the refrigerator unit BEFORE I order the new cooling unit (...figuring worst case if I couldn't get it out or if I broke something I could just buy a new refrigerator for ~$1600 and install it myself).

I'm going to order a replacement cooling unit. The online company sells REFURBISHED ones for ~$450. I'm told by the company that these will perform similar to the existing one that originally came with the refrigerator. OR, for ~$650 I could buy a brand new UPGRADED design that they say will have better performance and be able to keep the refrigerator colder especially when it happens to be 100 degrees outside. They also say it should last longer.

Do any of you have any experience or opinion as to how much better the NEW replacement unit might be over a refurbished unit (in terms of its ability to keep the refrigerator cold)?

Thanks in advance!
Chris

[wa8yxm]

SJ-Chris wrote:
Summary: When replacing the cooling unit on your refrigerator, would you go with a refurbished unit ($450) or a new unit ($650)??

Normally I have no issue with Refurb stuff. for I know it's been tested and works.. BUT in this specific case NEW.. always NEW Never Refurb.

The original failed because (most likely) The metal of which it is made got old and tired.. and the REFURB likely did as well. The odds of failure in another spot bother me.

[SJ-Chris]

General question about refrigerator operation....

(I'm trying to determine if in fact my cooling unit is dead)

Question: If the heating element is fine and it is heating the unit/stack AND if the cooling unit is good, then is there any way that the refrigerator would NOT be getting cool??

I know that the heating element was working prior to me pulling the refrigerator but I was getting no cooling in the fridge whatsoever.

Let me know.
Thanks!
Chris

[Boon_Docker]

When a thermistor goes bad it causes the fridge to become extremely cold. If the "heating element" was getting hot and the fridge not cooling then the cooling unit is shot. Time to replace it.

[SJ-Chris]

UPDATE!

Well, I *thought* I had everything figured out and was about to order the new cooling unit ($650) and a new heating element ($35). But I decided to test my thermistor. Yes, I know NOW that that should be among the first things to check...but I didn't know that until now. (And now I have my fridge out and the original cooling unit removed).

I put an ohm meter on the thermistor to check the resistance. It is coming back as an open (infinite resistance...as in the ends aren't connected). I am very confident in my measurement. If I touch the ends of my ohmmeter together it shows me Zero ohms. If I check a simple piece of wire, it shows me some ohms. But when I probe the two contact points on the thermistor it comes back as infinite (not connected). Do thermistors fail like that? (Note: Yes, I am very confident that my probes are making contact with metal inside the thermistor connector.)

Question: Would that have any chance of causing ZERO cooling inside my fridge and freezer??? I have (before removing the fridge and cooling unit) tried on propane for hours and also plugged in to 110v for hours and got ZERO cooling.

Suddenly, I'm not sure whether or not my cooling unit is bad. How else can I test this system to figure out what is bad?

From my discussion with the online "cooling unit" tech, it sounds like the 3 main components that can go bad are:
1) The heating element (although mine got hot so I don't think it is the problem.
2) The cooling unit.
3) The control panel/board.

I guess "bad thermistor" could be on that list too.

Do I need to put it all back together, unplug the thermistor, and re-test the refrigerator to see if it works? If it really is infinite resistance on the thermistor, then isn't that the same thing as having it unplugged??

Could it be the control board? How often do those go out? (is it rare or common?)

Thanks!!
-Chris

[Old-Biscuit]

SJ-Chris wrote:
One thing I didn't check (...and probably should have!)...but I'm learning as I go here...

I didn't check the thermistor. My understanding is that if those go bad, it will make it (usually) so that it doesn't stop cooling.

Does a failed thermistor ever result in ZERO HEAT in the refrigerator?? I'm guessing no but would like to hear what you think...

Thanks!
Chris

PS: I absolutely LOVE this forum and appreciate the RV community and the help they provide always!

If thermistor fails fridge SHOULD go into 'Limp' Mode which allows for continuous cooling
That is why unplugging thermistor leads at circuit board will make fridge to operate continuously and cause VERY low temps in freezer AND Food compartment IF--IF cooling unit is capable of cooling

If fridge dose cool down...replace thermistor
If it doesn't...force cool by direct energizing element lead

But this is ALL mute....cause you have already removed cooling unit so NO testing can be done

Buy NEW cooling unit and new element

[SJ-Chris]

One thing I didn't check (...and probably should have!)...but I'm learning as I go here...

I didn't check the thermistor. My understanding is that if those go bad, it will make it (usually) so that it doesn't stop cooling.

Does a failed thermistor ever result in ZERO HEAT in the refrigerator?? I'm guessing no but would like to hear what you think...

Thanks!
Chris

PS: I absolutely LOVE this forum and appreciate the RV community and the help they provide always!

[rhagfo]

Ron3rd wrote:
The Amish units have gotten a lot of praise here. There's one in particular that's supposed to be the best, can't remember the name but others will chime in. You said you're handy and that's great. It's not rocket science

This is where I have gotten both of my replacement cooling units. One was for the refer in out 86 King of the Road. The other was for our current 5er. The latest was a new improved design, and works great. Great coustomer service.
RV Cooling Unit Warehouse

[Old-Biscuit]

The DM2852RBX was a short production run (built outside the US) while Dometic built a New Production Plant in Elkhart.

Here is a NEW Amish Built replacement cooling unit for your model
RV Cooling Unit Warehouse....$665

They also have 'reman' for $545

I would go with NEW

And a new element also while access is wide open


Question:

What troubleshooting did you do?
Disconnect thermistor
Direct wiring of element to force cool the fridge

[SJ-Chris]

Seems like a good time to also change out the heating element, right??? It is 5 years old. Putting in a new heating element only costs ~$35 and I've already got it all apart anyways so it is simple to do. No brainer to also replace the heating element, right? (...unless you tell me those last forever and I should just keep the existing one...)

Thoughts? Thanks!
-Chris

[time2roll]

I am generally in the new camp unless you plan to sell the RV within the warranty period of used.

[SJ-Chris]

Ron3rd wrote:
The Amish units have gotten a lot of praise here. There's one in particular that's supposed to be the best, can't remember the name but others will chime in. You said you're handy and that's great. It's not rocket science

Yes, the online cooling unit company sells new Amish built units. The salesperson (who was incredibly helpful and sounded like he has been in the business for 30 years) says it performs much better (keeps things cooler) than the refurbished units. BUT...I can't tell if that is just a sale's pitch or not. 🙂 That's why I'm checking here to see if anyone has any experience between the two. I certainly don't mind spending $200 extra *IF* it is going to actually cool better (and last longer).

-Chris

[agesilaus]

Do you mean Omish or Amish?

As for the fridge this is what happened to our Norcold. It was working fine on both 120 and propane. Then one day it was not. After various troubleshooting I narrowed it down to the 'eyebrow board', the one in the door itself. Replaced that and has been working great. $150 on Amazon. I got some excellent advice here and never would have figured it out without it. That dealer is not to be trusted.

[Ron3rd]

The Amish units have gotten a lot of praise here. There's one in particular that's supposed to be the best, can't remember the name but others will chime in. You said you're handy and that's great. It's not rocket science

[RobWNY]

I just watched a mobile RV repair Tech do this on Youtube. Here is the link Refrigerator Cooling Unit Replacement. Maybe it will be useful to you. He did say he had trouble finding a parts distributor that had a new unit to sell to him.

[12th_Man_Fan]

You need to check into the Amish built cooling units. The quality of these units are supposed to be superior to any OEM unit.

If you continue on the route you are going I would say to use the new unit rather than the rebuilt one since your rig is only 5 years old, It will probably be in service many more years, and I just don't trust most rebuilt products.