Carrier 69NT40-561-399 Operation And Service Manual page 90

CODE TITLE
P5-1 Supply Probe Test
P5-2 Return Probe Test
P5-3 Evaporator Fan Di-
rection Test
P5-7 Primary vs Sec-
ondary Evaporator
Temperature Sen-
sor Test
P5-8 Primary Evapora-
tor Pressure Trans-
ducer Test
P5-9 Suction (Evapora-
tor)
Transducer Test
T-365
DESCRIPTION
This test if for units equipped with secondary supply probe only.
The temperature difference between primary supply probe and secondary
supply probe is compared.
Test passes if temperature comparison falls within the specified range.
If this test fails, "P5-1" and "FAIL" will be displayed. If both
Probe tests (this and the SUPPLY/RETURN TEST) pass,
because of the multiple tests, the display will read "P 5"
"PASS."
For units equipped with secondary return probe only.
The temperature difference between return temperature sensor (RTS) and
return temperature sensor (RRS) probe is compared.
Test passes if temperature comparison falls within the specified range.
1. If this test fails, "P5-2" and "FAIL" will be displayed. If both
Probe tests (this test and the SUPPLY/RETURN) pass,
because of the multiple tests, the display will read "P 5,"
"PASS."
2. The results of Pre-trip tests 5-0, 5-1 and 5-2 will be used to
activate or clear control probe alarms.
With evaporator fan running on high speed, measure the temperature differ-
ence between the primary supply and primary return probes. Turn the heat-
ers on for 60 seconds then measure the temperature difference between the
primary supply and primary return probes for up to 120 additional seconds.
This is a Pass/Fail test. The test passes if differential of STS is 0.25°C higher
than RTS.
Test P5-0 must pass before this test is run.
This is a Pass/Fail test of the primary evaporator temperature sensor (ETS1)
and secondary evaporator temperature sensor (ETS2).
Test passes if secondary evaporator temperature sensor (ETS2) is within +/
- 0.5°C of the primary evaporator temperature sensor (ETS1).
This is a Pass/Fail test of the Primary Evaporator Pressure Transducer.
Test passes if suction pressure transducer (SPT) is within +/- 0 psi of satura-
tion pressure at current evaporator temperature. Also passes if SPT is within
+/- 1 psi of discharge pressure 6 hours after a power interruption.
Test P5-7 must pass before this test is run.
Units equipped with a secondary Evaporator pressure transducer.
Pressure
Test passes if suction pressure transducer (SPT) is within +/- 1.5 psi of the
evaporator pressure transducer (EPT).
Test P5-8 must pass before this test is run.
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