Running Refrigerator on Propane

[jerichorick]

I had two coils fail do to not leveling properly. The ammonia, as I understand it, is very caustic. If it collects and sits for a period of time it begins to eat at the inside of the coil. Eventually a pin hole develops and the refrigerant vents out, leaving a yellow residue on the coil. When not traveling level your rig or park where it is level. Even that food stop can be death to your fridge if you are not level enough.


Love my residential fridge. More forgiving.

[Wayne M]

Originally Posted by SarahW

Sorry, but I disagree. I like to keep the fridge running and my food at a safe temperature. Never a problem in several years of RVing.

As Sarah does. we did with our 2008 for 10 years. Left it running on propane going down the road The Norcold only had two settings, Propane or 110. We just left it in Auto Mode. I did abide by the 3˚ and 6˚ rule when parking for an extended period of time. For just short stops, well it was wherever we were but most rest stops and truck stops where within the limits. Driving is no problem as the liquid is sloshing around and is not puddled up in any bend.

Now we have a residential and don't worry about it. In any case we don't stay parked on a hill for any length of time.

Just my 2 cents.

[DryCreek]

Originally Posted by jerichorick

Love my residential fridge. More forgiving.

The residential refrigerators have their definite advantages, but the need for a larger battery bank and solar to keep them going for more than a short overnighter can end up costing more in the long run.

[jerichorick]

Originally Posted by DryCreek

The residential refrigerators have their definite advantages, but the need for a larger battery bank and solar to keep them going for more than a short overnighter can end up costing more in the long run.

More battery. Yes. Solar. Optional. If a replacement frig is in order, going with the upgrades is wort it, in my opinion. Better peace of mind and better food protection is the end results.

[old_engineer]

We had a 3-way in our previous trailer. I used the 12V heater when traveling but keep in mind you need a large gauge Aux line on the truck to handle the current without too much voltage drop. The 12V element on our drew 11 amps. Our 2106FBS is a 2-way so we run on gas when we are traveling. These things aren't as well insulated as household refrigerators and 6 hours traveling in 90+ degree temps can take the fridge temperature out of the safe zone. As long as you are moving there should be no issues with coolant flow. When stopped we try to find a level spot or one that slightly favors the side that the heating elements are on. If you look at the coils this is the direction the condensate flows back to the reservoir. Haven't had a problem yet and we go from flat earth to 6% grades regularly.

[BVThunder]

Years ago I asked a trusted mobile tech the question about how level the frig needed to be. He said if you can comfortably sleep at the angle of your unit. Then the frig is fine.

[jerichorick]

Originally Posted by BVThunder

Years ago I asked a trusted mobile tech the question about how level the frig needed to be. He said if you can comfortably sleep at the angle of your unit. Then the frig is fine.

I have known folks who sleep in a recliner. Not a good rule of thumb.



Incorrect leveling, or extended out of the frigs manufactures recommendations for 'level', over a periods of time may cause the exchanger to fail. Just my two cents. (Well, $1200 if I recall correctly plus labor.)

[SCVJeff]

Off leveling doesnt cause the fluid to eat the steel, but it could super heat it causing it to crystalize and clog the plumbing, once the damage is done, its done, and no amount of tapping, banging, rocking, or turning it upside down will cure a catistrophic clog. As for residential... to each their own. It simply doesnt work the way we dry camp

[LarryW]

Jeff, the rumors will persist that you can fix those clogs with hammers, shaking etc. no matter what you write.

[jerichorick]

Originally Posted by SCVJeff

Off leveling doesnt cause the fluid to eat the steel, but it could super heat it causing it to crystalize and clog the plumbing, once the damage is done, its done, and no amount of tapping, banging, rocking, or turning it upside down will cure a catistrophic clog. As for residential... to each their own. It simply doesnt work the way we dry camp

I'm not certain what you are saying here Jeff. Not disagreeing with you.


As I understand it, the ammonia based coolant will, in some mysterious way to me, gather in spots in the coil when the RV is out of level limits. Over time this will cause the coil to be eaten away from the inside out. I kind of see it as sun shining on one side and ice on the other. May be a bad analogy. If the ammonia doesn't flow as designed for cooling it will eat its container, so to speak. How close am I?


Thanks.
Rick

[Oldchinahand]

Rick, All,

I've already chimed in once as an unabashed supporter of gas absorption (GAR) refrigerators. Familiar with camper sized as a kid, responsible for industrial sized back in my haze gray and underway days, as labor relator for a large food retailer enjoyed discussing distribution center ammonia chillers with facility Director, and now enjoy maintenancing the one in our rig.

Their biggest advantage is that they are hugely energy efficient compared with compressor driven freon systems.

Their biggest disadvantage vs compressor driven systems is that it takes them much longer to cool from ambient temperature.

Here are two really good reads discussing GARs. No, the cascade tubes will not get "eaten", but in some out of level situations, the boiler can potentially overheat and sodium chromate, an anti corrosive, may precipitate out as crystals that can plug the cascade. One thing I did not know until researching all this, is that since 1983, boilers have been fitted with water jackets that reduce the chance of the boiler overheating.

Why does the refrigerator need to be level

http://sundancecustomrv.com/Ammonia%...rigerators.pdf

Fascinating reads. Hope they enable you to peer through the fog of opposing opinions.

Fair Winds and Following Seas

[DryCreek]

Originally Posted by Oldchinahand

responsible for industrial sized back in my haze gray and underway days, as labor relator for a large food retailer enjoyed discussing distribution center ammonia chillers with facility Director

Ahh, the Lithium Bromide chillers! We had to study them as a part of MM "A" School, and for advancement exams, but the 688's only had R114's.

While growing up in Corpus Christie TX, I worked for an AC/R guy and we had to service the ammonia compressors at a large ship chandlery. It was "interesting" work, but not so exciting after a corroded pipe going to the condenser coils ruptured and killed the two night guys working there....

[SCVJeff]

Originally Posted by LarryW

Jeff, the rumors will persist that you can fix those clogs with hammers, shaking etc. no matter what you write.

thats all they are is rumors, find me one that has me one that has.. Occasionally burping them will mix and help clear them “they” say, but in the 12years+ I’ve been in these and other RV forums, no one with cooling issues has come back saying a burp has fixed their problem, only extended it.

As for beating them with a hammer.... really? Think about it.. The #1 failure with these cooling units are welding fractures, and someone is going to beat it with a hammer? Right....

[jerichorick]

Originally Posted by DryCreek

Ahh, the Lithium Bromide chillers! We had to study them as a part of MM "A" School, and for advancement exams, but the 688's only had R114's.

While growing up in Corpus Christie TX, I worked for an AC/R guy and we had to service the ammonia compressors at a large ship chandlery. It was "interesting" work, but not so exciting after a corroded pipe going to the condenser coils ruptured and killed the two night guys working there....

Wow! So sad. Glad you missed the excitement.



DryCreek, take a road trip to Dry Creek, LA during craw fish harvest time and ask a local where the best are served. YUMMMM!!!!

[Old Crows]

Excellent posts Guys! Now I'm wondering what the 'sales weenies****' are saying about the positives of compressor fridge ownership vs. those nasty, unreliable, old school "GARs".

{{{{ Sort of like those new fangled 'instant' water heaters...… "You are gonna save, save, save!!!!" Really now?}}}}} Skeptical Crow here.


I think I'd have to tape my beak shut with Gorilla Tape!!!!


As an aside.... from reading a number of forums over the last 10 years, I appears to me that Dometic and Norcold have been building have a QA/QC problem. Good designs.... poorly executed. I say so as many (if not all the problems) appear to stem from poorly designed mother boards; sketchy fusing; & electro-mechanical failures and NOT due to problems with the actual 'cooling cycle' components.


These problems are compounded by the poorly placed components that defy repair unless you yank the thing out of the RV. At that point, it is cheaper to just get a new one most of the time. Especially if the unit has a number of years on it. That's really poor engineering and design work. You shouldn't have to yank a fridge to access a fuse or component hidden on the back of the fridge or remove half of the front section to access the same.


It is no wonder that RV salesmen can talk about the benefits of compressor driven units conveniently forgetting that you are now tied to solar, batteries, or 110V (except in some WBGOs that do not have the 110V AC rigged up!). Single source of energy. No redundancy.


The actual benefit to the mfgr is that they can slap in a 'compressor' unit in an RV. No cooling vents to put in. No LP to run. Just 'plug' it in. It's a time and $$$ saver for them with the expectation of few call backs. (Or, or so they think....)


I guess another point would be that the weight gain of solar panels, wiring, controllers and hefty batteries off sets the 'lighter????' compressor jobs. Doubting they are lighter... but for the sake of argument, there's an additional weight penalty for solar & larger batteries. Convenient? Yes. But what are you going to do when the sun doesn't shine for a week? I know.... watch your ice cream leak out of the freezer door.

I may be 'old school' but there is a lot to be said to support GARs. They are used all over the world for many, many purposes because they are efficient, reliable and proven technology.


Just Crow ramblings.... too hot to fly!

******* Nothing like trying to carry on a technical conversation with an 30 something that missed 50% of their HS physics and chemistry classes.....

[Old Crows]

Afterthought (and a cup of coffee)….. So? How do they heat and cool the International Space Station???? Solar driven compressors!!! NOPE!!!! A variation on the GAR theme...

"The station has been continuously occupied for 17 years and 238 days since the arrival of Expedition 1 on 2 November 2000." Has the cooling system required Maintainence? Yes. But it's still chugging along silently and efficiently doing its duty.

https://www.space.com/21059-space-st...fographic.html

[Old Crows]

RE: DryCreek's comment about the hazard posed by ammonia cycle & broken pipes.

You Sir, have reminded me of a past life. Pardon my geezing…. About 33 years ago, I worked as a radiation safety officer for the Navy at the Naval Surface Weapons Center. NSWC was started back in the 19th century to test naval guns, etc.. Lots of interesting 'stuff' and waaaay cool things to see and play with. But much of it ancient and sketchy by 1980's safety standards.

NSWC had a gigantic (I mean the biggest thing you would ever see!) x-ray unit build in a small hanger. The head was on a gantry to position it anywhere over the bay. The transformers and switch gear were in a 'shed' attached to the end of the building. Master control room on the second deck overseeing the 'bay'. You set everything up here and then went to another shed outside the building to 'fire' the shot. (Just like your dental tech does....) This was a monster! So big that they brought in the Apollo rocket motors to x-ray them (NDT) for faults. Kinda cool!

This was an ancient GE unit probably built in the '30s.... maybe late '20s. Wiring was all that cloth covered stuff with 'post and eye" connectors Specially built to do NDT radiography on things like 16" gun barrels and boat load of other big things.

Control panel looked like the movie set for Buck Rogers serials or Frankenstein (or Bride of...). This dinosaur need lots of cooling. So GE put in their best, efficient & proven technology, a Sulphur Dioxide system. Big DANGER signs! Lots of other signs saying you will die a very slow and painful death if there's a leak and you would much prefer getting zapped by X-rays.

Even 'mothballed', it was very spooky surveying that unit. Hadn't been used since the Apollo testing. Vacant. Dusty. Industrial smelly. It was falling into a Chernobyl-esk existence. So spooky that folks would detour & walk a block around to avoid it, even thought the X-ray unit had long since been shut down.

[DryCreek]

Originally Posted by Old Crows

NSWC had a gigantic (I mean the biggest thing you would ever see!) x-ray unit build in a small hanger.
Specially built to do NDT radiography on things like 16" gun barrels and boat load of other big things.

Too bad they can't loan it out to Dometic/NorCold to allow them to shoot the cooling systems of failed units! Having an inside look at where the blockage is could go a long way to design improvements. Eliminate common failure choke points and you can enhance the reliability of the refrigeration cycle. A win-win for everyone.


(See, any thread that gets off track can be coaxed back onto the rails!)

[SarahW]

Originally Posted by DryCreek

(See, any thread that gets off track can be coaxed back onto the rails!)