P6/Pc 03(High Pressure Protection Or Low Pressure Protection Diagnosis And Solution) - Pioneer QUANTUM INVERTER Series Service & Troubleshooting Manual

7.13 P6/PC 03(High pressure protection or Low pressure protection diagnosis and solution)

Description: Outdoor pressure switch cut off the system because high pressure is higher than 638 PSI or outdoor
pressure switch cut off the system because low pressure is lower than 19 PSI, the LED displays the failure code.
Recommended parts to prepare:
• Connection wires
• Outdoor PCB
• Refrigerant
• Pressure switch
• Outdoor fan
Troubleshooting and repair:
High pressure protection
Are the high pressure switch
and main control board wired
correctly?
Yes
Is the high pressure
protector defective?
Method : Disconnect the plug.
Measure the resistance of the
high pressure protector. If the
protector is normal the value is
0. Does a problem still exist ?
Yes
Is the outdoor ambient
temperature higher than
122°F ?
No
Check if the outdoor unit
ventilation is good
Yes
Is the outdoor fan running
properly ?
Yes
Is the heat exchanger dirty ?
No
Replace outdoor main board .
Is the problem resolved?
No
Check whether the refrigerant
system is functioning properly
Troubleshooting

Connect high pressure switch
No
and main control board
No Replace high pressure protector
Yes Stop the unit until temps drop
NO
ventilation is configured properly
Please refer to the solution of the
No "Fan Speed is operating outside of
Yes Clean the heat exchanger
35
Ensure that the outdoor unit
normal range" malfunction.
(continued on next page)