Leveling The Refrigerator; When The Refrigerator Is Not In Use - Dometic RM1350M Installation & Operating Instructions Manual

refrigerator overview
absorption cooling system
In an absorption refrigerator system, ammonia is liquefied in the
finned condenser coil at the top rear of the refrigerator. The liq-
uid ammonia then flows into the evaporator (inside the freezer
section) and is exposed to a circulating flow of hydrogen gas,
which causes the ammonia to evaporate, creating a cold condi-
tion in the freezer.
When starting this refrigerator for the very first
time, the cooling cycle may require up to four
hours of running time before the cooling unit is
fully operational.
The tubing in the evaporator section is specifically sloped to
provide a continuous movement of liquid ammonia, flowing
downward by gravity through this section.
Sodium chromate is used for corrosion protection (less than
2 weight % of the coolant).

leveling the refrigerator

Leveling is one of the requirements for proper operation with
absorption refrigerators. To ensure proper leveling the vehicle
needs to be leveled only so it is comfortable to live in (no notice-
able sloping of floor or walls).
Any time the vehicle is parked for several hours with the refrig-
erator operating, the vehicle should be leveled to prevent this loss
of cooling.
CAUTION
Do not park your RV on a slope for a longer period of
time. Absorption refrigerators use a gravity-flow system.
Being on an angle of more than a couple of degrees for ex-
tended periods of time stops the refrigeration and might
cause damage to the cooling unit.
If the refrigerator is operated when it is not level and the vehicle
is not moving, liquid ammonia will accumulate in sections of the
evaporator tubing. This will slow the circulation of hydrogen and
ammonia gas, or in severe cases, completely block it, resulting in
a loss of cooling.
When the vehicle is moving, the leveling is not critical, as the
rolling and pitching movement of the vehicle will pass to either
side of level, keeping the liquid ammonia from accumulating in
the evaporator tubing.

when the refrigerator is not in use

Any absorption refrigerator that is to be taken out of service for
an extended period of time should be turned off.
CAUTION
It is important that you do not leave the refrigerator to
run idle and/or unattended for days or weeks.
purging air from the lines
If the refrigerator has not been used for a long time - or -
the LP tanks have just been refilled, air may be trapped in the
supply lines. To purge the air from the lines, turn the refrigera-
tor off and on by pressing the ON/OFF button. If the flame is
not lit within 45 seconds, turn the refrigerator off and back on
again. This procedure can be repeated 3 to 4 times. If repeated
attempts fail to start the LP gas operation, check to make sure
that the LP gas supply tanks are not empty and that all manual
shutoff valves in the lines are open.
automatic cooling unit
cycling system and low
ambient control
The refrigerator has been design with an automatic cooling
unit cycling system that helps reduce frost build up in the fresh
food compartment. The first automatic frost reduction cooling
unit cycle begins 60 hours after turning "on" the refrigerator
(for best operational results the refrigerator should be turned on
anytime between 4 and 10 PM), and will last for approximately
120 minutes. Thereafter, the cycle will automatically repeat
every 48 hours as long as the refrigerator continues to run.
The automatic Low Ambient Control (LAC) ensures trouble-
free operation in low ambient temperatures (e.g below 50° F).
auto mode / gas mode
The refrigerator is equipped with a control system where the
user can choose to turn the AUTO mode on or off.
auto mode is turned on
The system is fully automatic which means that it selects the
most suitable energy source available, either 120V AC or LP
gas operation.
temporary gaS locKout
The gas operation will automatically be locked out for a period
of 15 minutes when the engine is switched off. This will pre-
vent gas operation e.g. when stopping at a refueling station.
auto mode is turned off (gas mode)
The system operates on LP gas only. The control system
activates the ignition system and makes one attempt to light
the burner. Note that the temporary gas lockout feature does
not work when the AUTO mode is turned off! Consequently,
when parking close to a gasoline pump all LP gas appliances
vented to the outside of the vehicle must be turned off. Other-
wise gasoline fumes from gasoline pumps might enter LP gas
appliance and these can then ignite from the burner flame and
cause a fire or an explosion.
6
!
FIRe OR eXPlOSION HAZARD. When refueling
or parked near gasoline pumps, when the AUTO
mode is turned off, shut off all lP gas appliances.
Failure to heed this warning could cause a fire or
explosion resulting in death or severe personal
injury.
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wARNINg