Thermo King UT-1200, Manual

Page: 48 / 169

Operating Instructions for Standard HMI Control Panel
48
• Heat Check - The ability of the unit to heat in
low speed is checked.
• Report Test Results - The test results are
reported when the Pretrip Test is completed. If
the Pretrip Test fails, alarm codes will exist to
direct the technician to the source of the
problem.
Pretrip Test Considerations
When performing a Pretrip Test, the following
issues should be considered.
• Whenever possible, run the Pretrip Test with
an empty truck box.
• If running a Pretrip Test on a truck loaded with
dry cargo, insure that proper airflow can occur
around the load. If the load restricts airflow,
false test results may occur. Also, units have
high refrigeration capacity which results in
rapid temperature change. Sensitive dry cargo
may be damaged as a result.
• If running a Pretrip Test on a truck that has
just been washed down, the extremely high
humidity inside the truck box may result in
false test results.
• If running a Pretrip Test on a truck loaded with
sensitive cargo, monitor the load temperature
during the test as normal temperature control
is suspended during pre-trip operation.
• Always perform Pretrip Tests with the cargo
doors closed to prevent false test results.
Performing a Pretrip Test
Starting a Pretrip Test
The Full Pretrip Test must be started with the unit
not running. Turn the unit on and clear all alarm
codes. Turn the unit off.
Turn the unit on and wait for the unit running time
hourmeters to be shown on the display. When the
unit running time hourmeters are shown on the
display, press and hold the PRETRIP Key for 5
seconds.
Figure 35: Pretrip Test
• A flashing Pretrip LED indicates that the
Pretrip Test is being initialized. When the
Pretrip Test starts, the Pretrip LED will glow
steady amber. The display will show the
Standard Display.
• The Amps Check Test will be preformed and
then the unit will start automatically. The
balance of the tests will be completed.
• The Pretrip Test will take about 20 - 30
minutes, depending on conditions.
IMPORTANT: The box temperature will vary
during the Pretrip Test. This is normal
operation.
• When the Pretrip Test is complete or if a
Shutdown Alarm occurs, the amber Pretrip
LED will turn off.
• Stopping a Pretrip Test: To stop a Pretrip Test
at any time, press the POWER OFF Key to
turn the unit off. This will generate Alarm
Code 28 Pretrip Abort. Other alarm codes may
also be generated. This is normal when the
Pretrip Test is halted before completion.
Starting a Engine Running Pretrip Test
The Engine Running Pretrip Test must be started
with the unit running. Turn the unit on and clear
all alarm codes. Allow the unit to start.
With the unit running, press and hold the
PRETRIP Key for 5 seconds.
Figure 36: PRETRIP Key