Carrier 69NT20-551-300 TO 399 Operation manual

Container Refrigeration
T--322 Rev --
OPERATION AND SERVICE
for
69NT20--551--300 TO 399
Container Refrigeration Units
r

OPERATION AND SERVICE MANUAL
CONTAINER REFRIGERATION UNIT
MODEL
69NT20-551--300 TO 399
Streamline Scroll

T-322
Safety-1
SAFETY SUMMARY
GENERAL SAFETY NOTICES
The following general safety notices supplement the specific warnings and cautions appearing elsewhere in this
manual. They are recommended precautions that must be understood and applied during operation and maintenance
of the equipment covered herein. The general safety notices are presented in the following three sections labeled:
First Aid, Operating Precautions and Maintenance Precautions. A listing of the specific warnings and cautions
appearing elsewhere in the manual follows the general safety notices.
FIRST AID
An injury, no matter how slight, should never go unattended. Always obtain first aid or medical attention immediately.
OPERATING PRECAUTIONS
Always wear safety glasses.
Keep hands, clothing and tools clear of the evaporator and condenser fans.
No work should be performed on the unit until all circuit breakers, start-stop switches are turned off, and power supply
is disconnected.
Always work in pairs. Never work on the equipment alone.
In case of severe vibration or unusual noise, stop the unit and investigate.
MAINTENANCE PRECAUTIONS
Beware of unannounced starting of the evaporator and condenser fans. Do not open the condenser fan grille or
evaporator access panels before turning power off, disconnecting and securing the power plug.
Be sure power is turned off before working on motors, controllers, solenoid valves and electrical control switches. Tag
circuit breaker and power supply to prevent accidental energizing of circuit.
Do not bypass any electrical safety devices, e.g. bridging an overload, or using any sort of jumper wires. Problems with
the system should be diagnosed, and any necessary repairs performed, by qualified service personnel.
When performing any arc welding on the unit or container, disconnect all wire harness connectors from the modules in
both control boxes. Do not remove wire harness from the modules unless you are grounded to the unit frame with a
static safe wrist strap.
In case of electrical fire, open circuit switch and extinguish with CO2(never use water).
UNIT LABEL IDENTIFICATION
To help identify the label hazards on the unit and explain the level of awareness each one carries, an explanation is
given with the appropriate consequences:
DANGER -- means an immediate hazard which WILL result in severe personal injury or death.
WARNING -- means to warn against hazards or unsafe conditions which COULD result in severe personal injury or
death.
CAUTION -- means to warn against potential hazard or unsafe practice which could result in minor personal injury,
product or property damage.
SPECIFIC WARNING AND CAUTION STATEMENTS
The statements listed below are applicable to the refrigeration unit and appear elsewhere in this manual. These
recommended precautions must be understood and applied during operation and maintenance of the equipment
covered herein.

Safety-2
T-322
WARNING
Beware of unannounced starting of the evap-
orator and condenser fans. The unit may
cycle the fans and compressor unexpectedly
as control requirements dictate.
WARNING
Do not attempt to remove power plug(s) be-
fore turning OFF start-stop switch (ST), unit
circuit breaker(s) and external power source.
WARNING
Make sure the power plugs are clean and dry
before connecting to any power receptacle.
WARNING
Make sure that the unit circuit breaker(s)
(CB-1 & CB-2) and the START-STOP switch
(ST) are in the “O” (OFF) position before con-
necting to any electrical power source.
WARNING
Never use air for leak testing. It has been de-
termined that pressurized, mixtures of refrig-
erant and air can undergo combustion when
exposed to an ignition source.
WARNING
Make sure power to the unit is OFF and pow-
er plug disconnected before replacing the
compressor.
WARNING
Before disassembly of the compressor make
sure to relieve the internal pressure very
carefully by slightly loosening the couplings
to break the seal.
WARNING
Oakite No. 32 is an acid. Be sure that the acid
is slowly added to the water. DO NOT PUT
WATER INTO THE ACID -- this will cause spat-
tering and excessive heat.
WARNING
Always turn OFF the unit circuit breakers
(CB-1 & CB-2) and disconnect main power
supply before working on moving parts.
WARNING
Wear rubber gloves and wash the solution
from the skin immediately if accidental con-
tact occurs. Do not allow the solution to
splash onto concrete.
WARNING
Make sure power to the unit is OFF and
power plug disconnected before removing
capacitor(s).
WARNING
With power OFF discharge the capacitor be-
fore disconnecting the circuit wiring.
WARNING
Do not use a nitrogen cylinder without a pres-
sure regulator. Do not use oxygen in or near a
refrigeration system as an explosion may
occur.
WARNING
Do not open the condenser fan grille before
turning power OFF and disconnecting power
plug.
WARNING
The Unit Power Plug Must Be Disconnected
To Remove Power From Circuit Breaker Cb1
CAUTION
Do not remove wire harnesses from control-
ler modules unless you are grounded to the
unit frame with a static safe wrist strap.
CAUTION
Unplug all controller module wire harness
connectors before performing arc welding on
any part of the container.

T-322
Safety-3
CAUTION
When condenser water flow is below 11 lpm
(3 gpm) or when water-cooled operation is
not in use, the CFS switch MUST be set to
position ”1” or the unit will not operate prop-
erly.
CAUTION
Pre-trip inspection should not be performed
with critical temperature cargoes in the con-
tainer.
CAUTION
When Pre-Trip key is pressed, economy, de-
humidification and bulb mode will be deacti-
vated. At the completion of Pre-Trip activity,
economy, dehumidification and bulb mode
must be reactivated.
CAUTION
When a failure occurs during automatic test-
ing the unit will suspend operation awaiting
operator intervention.
CAUTION
When Pre--Trip test Auto 2 runs to comple-
tion without being interrupted, the unit will
terminate pre-trip and display “Auto 2”
“end.” The unit will suspend operation until
the user depresses the ENTER key!
CAUTION
To prevent trapping liquid refrigerant in the
manifold gauge set be sure set is brought to
suction pressure before disconnecting.
CAUTION
The scroll compressor achieves low suction
pressure very quickly. Do not use the com-
pressor to evacuate the system below zero
psig. Never operate the compressor with the
suction or discharge service valves closed
(frontseated). Internal damage will result
from operating the compressor in a deep vac-
uum.
CAUTION
Use only Carrier Transicold approved Polyol
Ester Oil (POE) -- Mobil ST32 compressor oil
with R-134a. Buy in quantities of one quart or
smaller. When using this hygroscopic oil,
immediately reseal. Do not leave container of
oil open or contamination will occur.
CAUTION
Take necessary steps (place plywood over
coil or use sling on motor) to prevent motor
from falling into condenser coil.
CAUTION
DO NOT disassemble piston from NEW suc-
tion modulating valve powerhead assembly.
Doing so may result in damage to piston.
CAUTION
The unit must be OFF whenever a program-
ming card is inserted or removed from the
controller programming port.
CAUTION
Do not allow moisture to enter wire splice
area as this may affect the sensor resistance.
CAUTION
Do not allow the recorder stylus to snap back
down. The stylus arm base is spring loaded,
and damage may occur to the chart, or the
stylus force may be altered.
CAUTION
The inside mechanism of the recorder,
particularly the inside of the element housing
should never be oiled, however, control
mechanisms should be sprayed periodically
(every 60 days) with corrosion inhibiting CRC
3-36a or 6-66 or LPS no. 2.
CAUTION
Recorder element capillary tubing may be
bent, but never sharper than 1/2” radius;
extra care should be taken when bending
adjacent to welds. The bulb should never be
bent, as this will affect calibration.