Automatic Refrigerator Protection device

[hbn7hj]

I posted in another forum about installing an ARPrv.com refrigerator protection device in a class C. I got pilloried calling it snake oil and other bad things. Somehow I hit a nerve.

Anyhow, I have installed it in a class C, The refrigerator must be removed to install it in the Roadtrec C190P so I haven't done it yet. Most of my trips are through mountainous terrain being based in Tempe, Arizona. Anyone here interested in such a device, respond. I have two trips down, one to Grand Canyon and one to San Diego. The device does shut the refrigerator down when climbing and descending using boiler temp as the trigger. It shut down 6 times to and from the Grand Canyon and 8 times Going over the coastal mountains into San Diego.

The contrary view is that many of us have run these refrigerators for many years over mountains with no problems. I am installing an indicator light on the dash so I can tell when it activates. More trips will give me more info. Initial impression is it doesn't take much of a slope to activate. The activation temperature is adjustable.
Harry

[avanti]

Originally Posted by hbn7hj

I posted in another forum about installing an ARPrv.com refrigerator protection device in a class C. I got pilloried calling it snake oil and other bad things. Somehow I hit a nerve.

Anyhow, I have installed it in a class C, The refrigerator must be removed to install it in the Roadtrec C190P so I haven't done it yet. Most of my trips are through mountainous terrain being based in Tempe, Arizona. Anyone here interested in such a device, respond. I have two trips down, one to Grand Canyon and one to San Diego. The device does shut the refrigerator down when climbing and descending using boiler temp as the trigger. It shut down 6 times to and from the Grand Canyon and 8 times Going over the coastal mountains into San Diego.

The contrary view is that many of us have run these refrigerators for many years over mountains with no problems. I am installing an indicator light on the dash so I can tell when it activates. More trips will give me more info. Initial impression is it doesn't take much of a slope to activate. The activation temperature is adjustable.
Harry

What actual problem are you trying to solve, exactly?

[booster]

We have always been told driving is good for the frig to keep the refrigerant from puddling

I suppose on a long, all one way tilt, it could be just the opposite.

Very interesting.

All the more reason for a compressor frig, I guess. Most of us have enough trouble in hills.

[hbn7hj]

"What actual problem are you trying to solve."

The zinc chromate deteriorates at high temperature. When zinc chromate deteriorates the steel tubing is vulnerable to corrosion and obstruction. Once obstructed the refrigerator is ruined. The boiler temperature increases when off level.

I am surprised so few of us are aware of the consequences of off level operation during travel. We have all been told all is well if we are moving. All is not well if the hill is steep enough and long enough. The company website explains it better. You have to determine if they are correct. The link won't paste try ARPrv.com if interested.

The best solution is a compressor fridge. I will never have the battery capacity for a compressor fridge. Almost all of my travels deal with the mountains of the American west and I have taken to turning the fridge off on long descents or ascents. With this it takes care of itself.

How much mountain operation does it take to ruin a fridge? I don't know but I do know there are a lot of older units traveling mountain roads and still working fine.

I would be interested in someone else's experiences in using the device but I guess there are very few out there.
Harry

[avanti]

Well, I moved on to a compressor fridge quite a wile ago, so I have no dog in this fight. But, as you suggest, the claim that this is a problem in practice and not just in theory is a bit dubious. I had plenty of problems with lousy cooling due to uneven campsites, but for the decade than I owned one, the performance was uniformly mediocre--it never deteriorated.

Color me skeptical.

[peteco]

Originally Posted by hbn7hj

The device does shut the refrigerator down when climbing and descending using boiler temp as the trigger. It shut down 6 times to and from the Grand Canyon and 8 times Going over the coastal mountains into San Diego.
Harry

I put an ARPrv in my 2006 210 last spring before our trip out west. I have been nursing the fridge for several years and it is borderline at times maintaining cooling. Mods to vent baffling, sealing, and vent fans have worked well enough, but sometimes the temperature will creep up into the lower 40's in stressing heat conditions. I suspect the fridge had some damage from overheat before I got it 6 years ago. I put the ARPrv in to protect from overheat on long climbs and if I forget to turn the fridge off while parked off level. I wish I had put the money and time into replacing with a compressor fridge, which is what I will do when this fridge dies.

How do you tell that the ARPrv has shut the fridge down?

[hbn7hj]

"How do you tell that the ARPrv has shut the fridge down?"

I plan to use the alternator 12 volt output line which I have in the fridge compartment to drive an LED on the dash. It will go through the normally closed contacts of a relay whose coil is controlled by the 12 volt line between the ARP and fridge.

When the power is on to the fridge the LED is off. When the power is off the LED is on. When the engine is off the LED is off.

This leaves some relay coil current drain when parked so I may put a relay on that, too. The objective is no current drain when parked. The LED will only light with engine on and fridge off by ARP.

I asked ARP for a 12 volt source but they didn't give me one that could tell the difference between thermostat off and ARP off. Installation is tomorrow and the tough part is running a line from the fridge compartment to the dash. At the moment there is no way to leave the back of the fridge to underneath the coach. Nothing a little drilling can't solve!

There are other ways to do it without the alternator out line. ARP suggested using the relay that provides 12 volts to the heater. When it turns off pole 87a of the relay turns hot and that line can drive the LED. I think that means the LED would be on when powered by propane or AC which could be dealt with.

I would like to monitor The ARP actions and relate them to road grade (slope).
Harry

[InterBlog]

We purchased our Class B lightly used and within about a year, its Dometic 2351 3-way fridge that stopped cooling. Not wanting to have to modify our cabinetry, we replaced it with another of the same model (same dimensions). Bad move. The new one lasted only 20 months. It was still covered under warranty but it would have taken months to get authorized service (I checked). So we ate the cost of the second Dometic, replacing it with a Vitrifrigo, which has worked very well in all conditions ever since.

We never did any appreciable mountain travel with either of our old absorption fridges, unless you count going through areas like Wilkes-Barre on the way up the east coast. I don't know if the device being discussed in this thread will help with performance degradation. I wish y'all luck with that, but my preference is definitely the all-electric route.

[gklugie]

I have not heard of a refrigerator being damaged by an occasional mountain trip.

[JohnnyFry]

I have an ARP I purchased at FMCA from the engineer who developed it. It works as advertised. Surprise, the fridge will go off level sufficiently to trip out on an extended mountain grade. I also asked a Norcold rep what the limits of operation, it is: ±3° side to side and ±6° front to back. These measurements refer to the refrigerator front so reverse them to get the tilt of the RV. He also related that operating off level for several hours will damage the fridge and the damage is cumulative.

[JohnnyFry]

Harry, When the ARP trips out the lights on the front of the fridge go out, then the thermostat cuts off cooling they stay on. Take a signal from the fridge "on" light on the front panel.

[hbn7hj]

Never thought of tapping the control panel. If you wanted an LED visible from the back of the coach that would be the place to get it.

[Bruceper]

So this is only an issue if you are running your fridge while driving and going up or down a grade at more than 6 degrees? Sounds like a problem a dozen people have and doesn't warrant a badly built website to sell you something you don't need.

But I do appreciate the time lapse video of boiling water. I learned lots from it.

[kite_rider]

I had the NorCold 3-way mini fridge in my 99 VW Eurovan Camper and also in my '02 Eurovan Camper. This fridge was very finicky about being level to be functional, but otherwise was very dependable despite going up and down mountain passes literally hundreds of time!

The real issue with this fridge was the burner design. The original burner had an issue where rust and corrosion would build up and made it hard to keep a good flame. There is an updated burner that I picked up on E*Bay that made all of the difference.

I'm sure this wasn't the recommended operation mode for the fridge; but I would leave mine "on" in propane mode for *Months* at a time. While driving, parked on a slope, camping, and even short term storage. This was true on both fridges and after changing the burner I never had a single issue with either fridge.

[hbn7hj]

Your experience matches all others except those that caught fire and we don't hear much about that anymore. Surely there are scientific studies of sodium chromate and ammonia in water at 300psi I can't find them. How much time and temperature does it take to turn the corrosion inhibitor into a precipitate?

Certainly your average hill doesn't do it or we would have mountain country fridge failures which we do not seem to have. Does vibration inhibit the crystal forming precipitate. All off level fridge failures I personally know about (3) were done while not in motion.

I have the light on the dash to tell me when the fridge is off. It will be interesting to watch this year, Should I learn anything I'll post.

The light installation was a painful install but I got it done with the relays clicking properly. Now I need to reduce the brightness of the 12 volt LED. Not in my experience but I suppose a resistor in series will do that. Gotta do some reading.
Harry

[JohnnyFry]

Bruce: The front to back limit is actually +-3* which translates to a 6% grade which is not uncommon in the mountains. I have avtually seen my fridge trip out on a long grade... say Golden to the Eisenhower tunnel in Colorado.

[Bruceper]

Originally Posted by JohnnyFry

Bruce: The front to back limit is actually +-3* which translates to a 6% grade which is not uncommon in the mountains. I have avtually seen my fridge trip out on a long grade... say Golden to the Eisenhower tunnel in Colorado.

I stand corrected, but I still feel that this is a solution for an extremely limited audience.