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4–49
T-340
P6 Tests - Refrigerant Probes, Compressor and Refrigerant Valves:
Pass/Fail testing is performed for
the compressor, EEV, DUV, LIV (if equipped), ESV, and the refrigerant pressure and temperature sensors.
P6-0
Discharge Thermistor Test If Alarm 64 is active the test fails. Otherwise, the test passes.
P6-1
Suction Thermistor Test
If the Suction Temperature Sensor (CPSS) both is configured ON and is
invalid, the test fails. Otherwise the test passes.
P6-2
Discharge Pressure Sen
-
sor Test
If Alarm 65 is active any time during the first 45 second period, the test
fails. Otherwise, the test passes.
P6-3
Suction Pressure Sensor
Test
If Alarm 66 is active the test fails. Otherwise the test passes.
P6-4
Compressor Current Draw
Test
Compressor current is tested before and 10 seconds after start up. If cur
-
rent does not increase, the test fails. P6-7 is run at the end of P6-4. If this
test fails, P6-6 is skipped.
P6-5
Compressor Leak Test
Pre-trip P6-5 ensures that the compressor holds pressure. After compres
-
sor pump up and pump down, the compressor is turned off for 62 seconds.
When suction side pressure holds (less than 8 psi rise) for 10 seconds, P6-
5 passes, otherwise the Compressor Leak Test fails.
NOTE
P6-6 through P6-10 are conducted by changing status of each valve and comparing suction pressure
change and/or compressor current change with predetermined values. Tests will cause compressor and
condenser fans to cycle on and off as needed to generate the pressure required for individual Pre-trip
sub tests. The compressor will start in order to build discharge pressure, followed by compressor pump
down sequence. At the conclusion of compressor pump down sequence, the compressor will shut down
and the valve test will start.
P6-6
Economizer Valve Test
Passes if suction pressure increases a minimum of 4 psia when the valve
opens for 15 seconds.
P6-7
Digital Unloader Valve
Test
Passes if pressure and current changes are within 3 seconds of DUV
switch signal and either the pressure change or the current draw change
is above 5 psi or above 1.5A, respectively.
P6-9
Liquid Injection Valve Test (If equipped) Test passes if change of suction pressure is greater than 4
psia when the valve opens for 10 seconds. Otherwise, it fails.
P6-10
Electronic Expansion
Valve Test
The test records the suction pressure during the open valve position and
passes if the suction pressure increase is above 3 psi when the valve
opens for 10 seconds.
Table 4–7 Controller Pre-trip Test Codes