Fridge level - how critical

[norbert]

having been an hvac tech in another life, but no working experience on ammonia systems, i am puzzled...i fail to see logically why ammonia would crystalize, and if in fact it does... not change state once the unit is leveled....ammonia has an affinity for water ...it readilly dilutes...that is how the ammonia system works....i always fire up the refer b4 leaving on a trip ...and also run with it in operation while traveling(i like cold beer when i stop).... . while i am open to new knowledge... i just dont get it.....hoping for some new revelation...
norby

[Janssvt]

Thanks for the info, the web site. This question comes up alot. This is a great source of information!

[markdoane]

I don't know how ammonia crystallizes either. If it did, it would melt back to a fluid as soon as the temperature got above -107 F.
I thought the reason to keep the refigerator level was:
1. to keep the flame centered on the boiler
2. to provide for proper drainage of the condenser and evaporator.
I would appreciate knowing more about the ammonia crystallization phenomena. If someone can give a reference to a web page I would like to review it.

[85MH325]

Originally Posted by markdoane

I don't know how ammonia crystallizes either. If it did, it would melt back to a fluid as soon as the temperature got above -107 F.
I thought the reason to keep the refigerator level was:
1. to keep the flame centered on the boiler
2. to provide for proper drainage of the condenser and evaporator.
I would appreciate knowing more about the ammonia crystallization phenomena. If someone can give a reference to a web page I would like to review it.

gasrefrigeration.net

I don't know either, Don. I may have been wrong as well. According to the website above, perhaps my unit lost it's hydrogen rather than the ammonia crystalizing. I had loud boiling sounds, and even after repeated attempts at letting it 'stand on it's head', it wouldn't cool.

Here's the reason not to run your fridge unlevel (according to the website above):

Running While Not Level

The second biggest killer is running unleveled. When the refrigerator is operating, water moves around the pipes and flows down the coils on the back into the main storage tank. The pipes on the back all slope down from side to side. When the RV is off-level, one direction of the coil will be flowing up-hill and the water flow will stop. When this happens there is no flow to the boiler section and the water in the boiler pipe boils dry. The rust inhibitor dries up and blocks the boiler tube. If the unit is kept running the boiler pipe will get so hot that it will crack from the gas pressure inside the coils (450#). Now the cooling unit is really dead.

Never believe the stories that the newer units do not need to be run level? They are made to run more off-level than the older units BUT there is still a point where they will stop working. Always try to level you RV, as best you can, and if you have to park for a long time and cannot level the unit, shut down the refrigerator. It will keep the food cold for hours. Most of the newer units we repair have all been run unleveled and cracked the boiler. (This can be a very costly mistake)

Roger

[norbert]

once again we come full circle again.....how much off level is off level as to impede proper operation....

[markdoane]

Originally Posted by 85MH325

gasrefrigeration.net
Roger

Roger,

Thanks. Great refererence!

[Sav'h Steve]

My '90 Dometic frig was not doing a good enough job of cooling and the unit was level.

But I observed that the coils in the center of the freezer that are covered with stainless steel that you put your ice trays on to freeze was NOT perpendicular to the back of the freezer. It was tilted down (toward the door).

This did not allow the free flow of fluids and the temp esp. in the frig section stayed in the upper 30s to lower 40s.

The cure was to take off the ss tray. It has screws on the bottom of the plate and it slides out. Then according to http://www.rvmobile.com you had to pry it straight. This simple procedure made an immediate difference in the temp and it lowered by 5-8 degs in top and bottom.

From all I have read, I would agree with turning it off when temporarily out of level for > 30 minutes.

However it is not a concern to be out of level while driving down the road according to rvmobile because it is continuously shifting and that keeps the fluids moving. RVMobile is a great site BTW..

Steve
BTW: How many of you run the frig when between camping trips. I don't. Just crank it up the day before.

[jcanavera]

Originally Posted by norbert

once again we come full circle again.....how much off level is off level as to impede proper operation....

I guess its just a matter of how close you want to push the envelope. Sort of like how fast can you go around a curve before you lose control?

I've just always gone by the rule to get as level as possible. To me this means using my little round bubble level placed on the floor of the freezer compartment, and making sure that at least half the bubble is within the inner circle. That translated to my big outside level is half a mark from side to side...and that translates to one Lynx leveler block under each wheel on the low side.

Jack

[ipso_facto]

I have a '95 Dometic and it required almost perfect leveling to work. I never knew about this until I found out. Amazing. Even a little bit off and it doesn't cool.

Otherwise it cools really well. The freezer is coldest I've ever seen.