Operation; Controlled Atmosphere (Ca) Pre-Trip Inspection (Before Starting); Controlled Atmosphere (Ca) Starting And Stopping Instructions - Carrier 69NT40-489-100 Series Operation And Service Manual

10.1 CONTROLLED ATMOSPHERE (CA) PRE-TRIP
INSPECTION (Before Starting)
a. Required Materials
1. Pre-Trip Kit
2. Calibration Gas
3. CO Bottles (when required)
2
CARBON DIOXIDE ADDITION:
When a commodity requires the addition of carbon
dioxide to maintain set points, 100% CO
must be provided. Bottles can be installed inside or
outside the container. Provision has been made to
connect in either location (see Figure 56, page 89 or
Figure 57, page 90). CO
the container structure.
Set manifold pressure of the CO
system control will open and close an internal valve to
discharge gas into the container.
b. Container Preparation
Inspection:
Check the rear container doors and door handles for
proper operating condition. Check for proper installation
of labels on the container and refrigeration unit. Always
visually check the inside of the container for occupants
prior to closing the doors. Check rear door lock for
proper installation, and that the solenoid plunger is
unobstructed.
Container Curtain:
Refer to section 12.12, page 131 for container curtain
installation instructions.
Leak Check Container - (Curtain Installed):
DANGER
HAZARDOUS ATMOSPHERE INSIDE.
LOW OXYGEN INSIDE CONTAINER CAN
CAUSE DEATH.
Performing service on, or entering a CA
equipped unit can be extremely dangerous.
Refer to the Safety section of this manual
before servicing or entering the container.
Two connection ports are provided on the front of the
unit, see Figure 56, page 89. One is used for
pressurizing the container and the other is used for a
pressure gauge hookup to monitor leakage rates.
1. For static testing the acceptable leakage rate at 0.5
inch water gauge (12.55 mm) is 100 scfh (2.8 cmh) or
less.
2. For pressure decay testing, measure the time re-
quired for the pressure to decay from 2.0 inches water
gas bottles
2
bottles should be secured to
2
bottle to 20 psig. The
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SECTION 10

OPERATION

gauge (38 mm) to 1.0 inch water gauge (25 mm). The
acceptable time span is 105 seconds or more for a 40
foot container and 53 seconds or more for a 20 foot
container.
If either test results in unacceptable leakage rates, then
sealing of the container is required. These leakage rates
must be maintained or the Controlled Atmosphere (CA)
system will not be able to reach its set points.
Some areas to check for leaks are:
Check for installation of polysheet curtain.
S
Check the unit drain line. Fill with water, if
S
necessary.
Check the unit access panels.
S
Check unit/container box joint. Caulk if
S
necessary.
Inside the container, check floor drains, check
S
floor to side wall joint, floor to front bulkhead
joint, side wall to front bulkhead joint and
ceiling to front bulkhead.
Installation of filters:
Install new filters (intake air and sample air), refer to
section 12.7, page 127. Make sure all safety labels are
in place.
10.2 CONTROLLED ATMOSPHERE (CA) START-
ING AND STOPPING INSTRUCTIONS
Starting the CA system
The start up process will occur automatically at each
controller RESET or power--up, or whenever the
Controlled Atmosphere Run/Stop switch changes from
the Stop position to the Run position. The controller will
test the system components to ensure proper
operations. If any critical test fails, the appropriate error
message will display for 5 seconds and then the system
will restart.
1. Start refrigeration system. (Refer to section 4.6,
page 46)
2. Place the Controlled Atmosphere Start-Stop switch
(CAS) to the ON position.
3. The unit will enter the standby mode (standby indica-
tor will be illuminated) unless all of the following con-
ditions are met:
Return air temperature set point is below 25
S
degrees C.
The refrigeration unit temperature is
S
"in-range".
The CA air compressor has not run for three
S
minutes.
4. Set O and CO
2
111
set points.
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