Carrier Streamline Scroll 69NT20-531-300 - Manual (Page 48)

3-23 T-309
Table 3-7 Temperature Controller Pre-Trip Test Codes (Sheet 3 of 4)
NOTE
P7-0 through P10 are included with the “Auto2” only.
P7-0
High Pressure
S it h Cl d
NOTE
This test is skipped if the sensed ambient temperature is less than 7_C
(45_F), the return air temperature is less than --17.8_C (0_F), the water
pressure switch is open or the condenser fan switch is open.
g
Switch Closed
Setup: With the unit running, the condenser fan is de-energized, and a 15 minute
timer is started.
Pass/Fail Criteria: The test fails if high pressure switch fails to open in 15 min-
utes.
P7-1
High Pressure
Switch Open
Requirements: Test P7-0 must pass for this test to execute. Setup: The con-
denser fan is started and a 60 second timer is started.
Pass/Fail Criteria: Passes the test if the high pressure switch (HPS) closes
within the 60 second time limit, otherwise, it fails.
P8-0
Perishable Mode
Heat Test
Setup: If the container temperature is below 15.6 °C (60_F), the set point is
changed to 15.6 °C, and a 180 minute timer is started. The left display will read
“P8-0.” The control will then heat the container until 15.6 °C is reached. If the
container temperature is above 15.6 °C at the start of the test, then the test pro-
ceeds immediately to test P8-1 and the left display will change to “P8-1.”
Pass/Fail Criteria: The test fails if the 180 minute timer expires before the con-
trol temperature reaches set point. The display will read “P8-0,” “FAIL.”
P8-1
Perishable Mode
Pull Down Test
Requirements: Control temperature must be at least 15.6 °C (60_F).
Setup: The set point is changed to 0 °C (32_F), and a 180 minute timer is
started. The left display will read “P8-1,” the right display will show the supply
air temperature. The unit will then start to pull down the temperature to the 0 °C
set point.
Pass/Fail Criteria: The test passes if the container temperature reaches set point
before the 180 minute timer expires.
P8-2
Perishable Mode
Maintain Tempera-
ture Test
Requirements: Test P8-1 must pass for this test to execute. This test is skipped
if the DATAcorder is not configured or available.
Setup: The left display will read “P8-2,” and the right display will show the sup-
ply air temperature. A two hour timer is started. The unit will be required to
maintain the temperature to within + or -- 0.5_C (0.9_F) of set point until a Da-
taCORDER recording is executed. The recorder supply probe temperature run-
ning total (and its associated readings counter) will be zeroed out for the remain-
der of the recording period at the start of this test, so that the actual value
recorded in the DataCORDER will be an average of only this test’s results. Once
a recording interval is complete, the average recorder supply temperature will be
recorded in the DataCORDER, as well as stored in memory for use in applying
the test pass/fail criteria.
Pass/Fail Criteria: If the recorded temperature is within +/-- 0.5_C. of set point
from test start to DataCORDER recording, the test passes. If the average temper-
ature is outside of the tolerance range at the recording, the test fails and will
auto--repeat by starting P8--0 over.
P9-0 Defrost Test
Setup: The defrost temperature sensor (DTS) reading will be displayed on the
left display. The right display will show the supply air temperature. The unit will
run FULL COOL for 30 minutes maximum until the DTT is considered closed.
Once the DTT is considered closed, the unit simulates defrost by running the
heaters for up to two hours, or until the DTT is considered open.
Pass/Fail Criteria: The test fails if: the DTT is not considered closed after the
30 minutes of full cooling, HTT opens when DTT is considered closed or if re-
turn air temperature rises above 49/50_C (120/122_F).