Re: [A/S] Re: Leveling

["Jim Dunmyer" <jdunmyer@xxxxxxxxxxx>]

Phil,
 RV Mobile (http://www.rvmobile.com) does cooling system rebuilds for RV
refrigeration. From their technical area:
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Out of Level. If the cooling unit is operated in a stationary, out of level
position (on any heat source), it will eventually become permanently
damaged. Before we go any further, there is one more ingredient inside the
cooling unit: sodium chromate. The ammonia solution inside the cooling unit
is a mild corrosive, and sodium chromate is mixed with the ammonia solution
(ammonia and water) to neutralize the corrosive effects of the solution,
protecting the inner pipes of the cooling unit.

Since the cooling unit depends greatly on the effects of gravity for moving
the liquids and gases inside, running it off level and stationary causes
these liquids and gases to collect in unwanted areas and not be recycled
back to the boiler. The liquid level inside the boiler begins to drop and
become weaker. Eventually, the water in the ammonia solution begins to
vaporize with the ammonia and leave the boiler. At some point, the boiler
becomes dry and the temperature rises rapidly inside. The sodium chromate
which was once in solution with the ammonia solution is left behind and
begins to burn and permanently change state from a powder into a sort of
sludge that will eventually plug the perk tube. If left to cook long enough,
the sodium chromate will become as hard as steel. If the cooling unit were
"saved" from this out of level condition by being leveled, or the heat
source turned off, any sodium chromate that had changed state would not
return to a powder in solution with the ammonia solution. This makes it
possible to ruin a cooling unit a little at a time.

The new style boiler (see above) helps to prevent this cooking of the sodium
chromate, but it can still happen. More often than not, however, the liquid
inside the outer shell of the boiler vaporizes, causing the pipe that makes
up the outer shell to become super heated and crack, thus ruining the
cooling unit. So, although the double boiler effect of the new style boiler
may help prevent the perk tube from becoming plugged, it only gives the user
a little more time to recognize and correct a problem.

When traveling down the road, the liquids and gases inside the cooling unit
are sloshed around and don't collect in unwanted areas, making it all right
to travel with the refrigerator on.

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While *I* don't proclaim to be an expert, these guys make their living at
it.

                                                                    <<Jim>>