3-4
Pretrip Inspection
Operating Instructions
CRR-20 & CRR-40, September 1999
from the valve would be directed away from anyone ser-
vicing the unit. The valve will reset when this pressure
drops to 2758 kPa, 27.58 bar, 400 psig. The valve is non-
repairable and requires no adjustment. If the valve fails to
reseat properly, recover the refrigerant charge and replace
the valve.
8.
OVERLOAD PROTECTION. The condenser fan motor,
evaporator fan motors and compressor motor include
internal overload protection with automatic reset.
9.
PHASE SEQUENCE SELECTION. When the On/Off
switch is turned ON, the controller display shows “Phase
Check” while it determines the correct phase sequence.
Phase selection takes 50 to 80 seconds; or more on
extremely noisy power lines. The controller then ener-
gizes phase select contactor ABC or CBA to ensure prop-
er condenser fan, evaporator fan and compressor rotation.
Pretrip Inspection
Visual Inspection
The following visual inspections should be made before the
container is loaded:
1.
Visually check the unit for physical damage.
2.
Check the electrical connections in the unit control box,
making sure they are fastened securely.
3.
Check the conditions of wires and terminals. Repair or
replace if necessary.
4.
Check the refrigeration system for leaks. Inspect for evi-
dence of oil leaks at all joints and connections.
5.
Check the condenser and evaporator coils. Clean if neces-
sary. Use an air or water spray jet directed against the coil
from the air discharge side. Also inspect the condenser
fan grille for damage. If the grille is damaged or missing,
abnormally high head pressure may result. Repair or
replace the grille if necessary.
CAUTION: Air or water spray jet pressure should
not be high enough to damage (bend) coil fins.
6.
Check the mounting bolts on the unit, compressor and fan
motors. Tighten if necessary.
7.
Clean the defrost drains.
8.
Optional: Inspect water-cooled condenser-receiver tank,
water lines and fittings for water leaks. When water lines
are disconnected, also check to be sure that the water
drains completely from the condenser-receiver tank.
Report defective fittings and tanks that do not drain to a
technician.
9.
Optional: Check water level in humidity system tank.
Add only demineralized or distilled water to prevent plug-
ging of the atomizing nozzle.
10. Observe the unit for proper operation and functions during
Pre-load Operation.
Functional Inspection
To properly perform a Full Pretrip Test on units equipped with
the
µ
P-D controller, the container must be empty with the rear
doors closed.
1.
Start the unit (see “Starting the Unit and Adjusting the
Controller Setpoint” on page 3-6). A second sequence
start of the required loads occurs during initial start-up of
the unit.
• The status Indicator LEDs and display turn On and then
Off.
• The controller display shows “Phase Check” while it
determines the correct phase sequence. Phase selection
takes 50 to 80 seconds; or more on extremely noisy
power lines. Phase select contactor ABC and the electric
heaters, condenser fan and evaporator fans are energized
for 10 seconds. Phase select contactor ABC is then de-
energized. 30 seconds later, phase select contactor CBA
and the electric heaters, condenser fan and evaporator
fans are energized for 10 seconds. The controller then
turns OFF all unit loads and energizes phase select con-
tactor ABC or CBA.
• The setpoint and controlling air sensor temperature are
displayed.
• Controller energizes unit loads, starting the evaporator
fans. The condenser fan may also start (if required).
• If the controller calls for cooling, the compressor motor
starts. If the unit starts in Modulation Cool, compressor
start-up can be delayed up to 3 minutes while the evapo-
rator pressure regulator (KVQ) valve opens or closes to
the required setting.
• If the controller calls for heating, the electric heaters are
energized.
NOTE: If the unit does not start, turn the On/Off
switch OFF. Check power supply. Then repeat
step 1. If the unit still does not start, refer to
“Alarm Codes, Descriptions and Corrective
Actions” in the
µµ
P-D Controller chapter of this
manual. Be sure to wait up to 3 minutes for the
compressor to start.
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