ARP Refrigerator Protection

[RECVEH2005]

I've seen advertisements in the Escapees magazine for the ARP refrigerator protector which claims to protect Dometic/Norcold refrigerator boilers from overheating.

Have any of you installed this product? If so, what is your opinion of it?

Thanks in advance.

Mike

[MEXICOWANDERER]

Take 100 RV refrigerators. "X" percent are operated "X" hours per year. A bell curve if you will. So it would be difficult to assess one from another just by looking at the problem. The straw that broke the camel's back was my last Norcold. It would operate continuously for about 10-15 days then everything turned warm. Shut it down for two days, and it would work perfect for the next 10-15 days. Sal at Kool Fun in Irwindale CA., replaced the cooling unit under warranty twice with brand new cooling units from Norcold. When the third cooling unit did the same thing, it was pitched out of the emergency exit. This thing had an icemaker which promptly plugged-up even though DISTILLED water was used exclusively. This grade of garbage is polar opposite from Swedish Servel refrigerators which lasted several decades used 24/7.

You'd couldn't give me a gas refrigerator now. I'm still fuming over the hundreds and hundreds of dollars in spoiled food and endless needless shopping trips. Bah Humbug.

[dougrainer]

IAMICHABOD wrote:
WOW such ire and name calling,it must be a sore subject.....

I know that it has been a problem with this type of Refrigerator other wise there would not be so many cottage industries repairing them.

With the hundreds of thousands of these made what percentage fail. If mine fails I will replace it,but at 10 years of poor use and no problems, I will save my money,the damage has been done so I am told by the experts here:R

BTW Doug they are told and shown a video,look at about 11:16 min, on proper leveling.....as always when Rental comes up people talk about things they know nothing about.

There are tens of Millions RV absorbsion refers out there. They may watch a Video, but will forget it once they leave. COST of Refer repair was 1 of the factors in why we gave up on RV rentals years ago. I KNOW all about rental's and know the mindset of the users. Doug

[dougrainer]

IAMICHABOD wrote:

fj12ryder wrote:
It would be interesting to know how many RV fridges quit working due to being out of level for extended periods of time. I know this topic has come up before and several people chimed in, mostly truck campers BTW, and commented that their fridges were still working fine after many years. I do wonder if the problem isn't being overstated.

I also would like to know,I know of one that failed after 7 years of continuous use,in a rear sloping driveway.HERE

My 10 year old Former Rental,and we all know how they are treated,works very well and gets ready to put things in the freezer and refrig in about 6 hours.

A while back and I was at El Monte RV and talked to the service manager and I asked him about the problems that they may have had and he told me that in the 10 years that he had worked there he had never had a Refrigerator fail. In that time I would guess that they have had a few hundred RVs thru there and not one failure and he hasn't had one come back after a sale for that problem. Could it be that the constant movement of a rental helps?

Constant movement of a rental? Hardly. Remember, the MOST COMMON problems with Rental RV's ARE Rental customers. They have no clue how to operate the RV and could NOT care if the refer is level. Besides, they were probably never told about level operation when they picked up the rental. Doug

[Chris_Bryant]

There are 2 main reasons* an absorption unit can fail- it can leak, or it can become blocked.

There are 2 reasons it can become blocked, manufacturing defect- a bit of welding slag left in the unit, and the sodium tetrachromate being overheated and solidifying, blocking the boiler. The first problem will normally manifest itself in the warranty period, the second is always due to off level operation**

Leaking is usually due to internal corrosion of the evaporator, internal corrosion of the boiler, or stress fractures at the boiler. The boiler failures are usually due to overheating, often caused by off level operation.***

I have rebuilt literally hundreds of these refrigerators, probably half due to blocked units.

*There is another failure mode which is very hard to diagnose, and that is caused by overheating producing another gas, which displaces the hydrogen. The chemical theory behind that is above my pay grade.

**This failure mode is usually gradual, a slow decrease in performance.

***One thing about off level operation- the ARP really doesn't care how level the unit is, and bottom line is level is just a metric we can measure easily. What matters is the boiler temperature, which needs to be high enough to vaporize the ammonia, but below the boiling point of water. If the refrigerant is circulating, it doesn't matter about level.

[fj12ryder]

It would be interesting to know how many RV fridges quit working due to being out of level for extended periods of time. I know this topic has come up before and several people chimed in, mostly truck campers BTW, and commented that their fridges were still working fine after many years. I do wonder if the problem isn't being overstated.

[pianotuna]

Hi,

Only one post in the entire thread is wishy washy about the ARP. That person wanted "proof" that it works. Personally I could not wait to have one. No more driving in circles in parking lots to find the flattest spot for me!

RECVEH2005 wrote:
Well, this discussion has been a good education for me, the original poster. Unfortunately, there is NO access to the rear of my fridge at all; it would have to be pulled out from inside to access the rear of the unit (I cannot understand why it was designed that way!) The trailer is 3 years old - I think I have to weigh the part & labor cost of having an ARP unit installed on a 3 year-old Norcold fridge against the estimated remaining life of the fridge.

Mike

[RECVEH2005]

Well, this discussion has been a good education for me, the original poster. Unfortunately, there is NO access to the rear of my fridge at all; it would have to be pulled out from inside to access the rear of the unit (I cannot understand why it was designed that way!) The trailer is 3 years old - I think I have to weigh the part & labor cost of having an ARP unit installed on a 3 year-old Norcold fridge against the estimated remaining life of the fridge.

Mike

[dougrainer]

johnhicks wrote:
> difficult to install without pulling the refer.

That's for sure. I got it after a couple hours of shaved knuckles. It probably would've been easier to ease the reefer out a few inches.

Yes, It is one of those times that in hindsight it would have been easier. Doug

[johnhicks]

> difficult to install without pulling the refer.

That's for sure. I got it after a couple hours of shaved knuckles. It probably would've been easier to ease the reefer out a few inches.

[LarryJM]

timmac wrote:
How bout just installing a small button fan and run it while traveling down the road, would this work as well without dishing out 195 bucks ?

No what the ARP system does is to basically not allow the liquid in the boiler tube to get too hot due to lack of circulation and or volumetic flow which causes the liquid to get hot enough that the Al Chromate (I think that's the coolant/heat transfer liquid) crystallizes out and is deposited on the interior of the boiler tube. What this does is reduce the concentration of that chemical in the ammonia mix and also restricts the flow of the liquid thru the boiler tube where the heating occurs. This is somewhat analgous to Plaque and hardening of the arties in a human, it's cumulative and when has restricted flow enough your refer dies or the human has a heart attack. This boiler tube temp issue have very, very little to do with the ambient temps or external fans. The external fans and ambient temps mainly are an issue in reducing the temp of the fluid/gas mix after it has gone tru the evap coils at the top of the refer so that the mix entering the boiler area at the bottom of the frig is all liquid and not a mix of liquid and gas.

DISCLAIMER: I think I have all the above correct, but not being an actual refer expert I claim the 5th if I got anything too far wrong in the above info. Some might not be 100% technically correct, but I think the general "GIST" is there and fairly accurate.

Larry

[Chris_Bryant]

Salvo wrote:
I don't see any point in those questions.

The point- without simply seeing what the ARP does, what temps would you use om your $15 gadget. The point is there is more than just parts, and while an arduino could do the job, there is considerable development put in this product, with a ton of knowledge about the issues, so blowing it off with "I can build it for $15" is, in my opinion, somewhat disingenuous, as you make it sound like a simple limit switch. Your graphs simply show normal operation.

[dougrainer]

"No, I DO understand the basic principle of an absorption type unit. Not intimately, but I do better than most RVers. But my understanding of the RV refrigerator has nothing to do with this. You are missing the point of my questions. What I would like to know are more data related to how long out of level, how much out of level causes the problem. In the video, they tipped the unit around 20 degrees to demonstrate temperature rise. GOOD GRIEF! If my RV is tipped 20 degrees, I have more of a problem than an overheating refrigerator! I sometimes park on a slope for a while before I get it level, maybe 2-4 degrees. How does this affect the temperature? I pull a little nose high for long periods - maybe 1-2 degrees. Does this cause a problem severe enough to justify adding another system to the RV?
There are two questions here - fire hazard and longevity of the unit. I want to know the data for both it".

Fire Hazard is extremely rare. I know the doomsayers on these forums talk about the Norcold 1200, but ACTUAL DATA or ACTUAL reports on the Leaking CU caused a fire is almost non existent. It always seems some Fire official that has NO training will state without proof that the refer caused the fire. OK, The REFER caused the fire. But what WAS the cause? Birds nest caused the LP flame to ignite? Leaking LP at the various connections caused the fire? Short in the 120 wiring?
Now Longevity---How long unlevel? ANY time unlevel will cause a microscopic blockage. OVER time, all those times you were out of spec off level, those Microscopic blockages accumulate and cause cooling problems. THAT is one reason the ARP is a good thing to have. I don't have "data". Just 37 years of training and working on RV refer's and systems and numerous hands on Factory training by Norcold and Dometic. Doug

[timmac]

How bout just installing a small button fan and run it while traveling down the road, would this work as well without dishing out 195 bucks ?

[DFord]

The common causes of RV fires video by Mac the Fire Guy

The number two cause Mac lists for the cause of RV fires is the refrigerator - especially the 4 door Norcold models. Often the refrigerator is next to the door. Once your RV catches fire, you have less than one minute to save your life before it will be totally engulfed.

This ARP device is cheap insurance.