P7 Tests - High Pressure Tests: Unit is run at full capacity without condenser fan running to make sure that the HPS opens and closes properly.
| P7-0 High Pressure Switch (HPS) Opening Test |
| Test is skipped if sensed ambient temperature is less than 7.2 C (45 F), return air
temperature is less than -17.8 C (0 F), or the water pressure switch is open. With the unit running, the condenser fan is turned off and a 900 second (15 minute) timer is
started. The right display shows Discharge Pressure if the sensor is configured and valid, else Discharge Temperature. The unit needs to disable Discharge Pressure limit and
enable Current Limit checks. The test fails immediately if: -Ambient Temperature Sensor invalid -Composite Return Temperature Sensor invalid -HPS is open The test fails if: -HPS fails to open before 900 seconds total test time. -Evaporator or Compressor IP Alarm. -Calculated Dome Temperature exceeds 137.78 C (280 F). -Discharge pressure exceeds 370 psig. -Compressor Current exceeds limits The test passes if HPS opens within the 15 minute time limit. |
