Fault Code Lookup

HVAC Sales Master
29L
High Refrigerant Pressure Lockout
This code typically points to
  • High-pressure control opened three times in same call
  • Excessive refrigerant charge
  • Failed indoor blower motor
  • Dirty return filter
  • Dirty indoor coil in heating
  • Failed outdoor motor
  • Dirty outdoor coil in cooling

Next checks to confirm
  1. Evaluate cause of high-pressure condition
  2. Inspect charge, indoor airflow, outdoor fan, and coil cleanliness per operating mode

Escalation
After HPC opens 3 times during same call, UODC locks compressor out and Control Center displays high-pressure lockout
Reset behavior
Manual reset only — disconnect electrical power to both indoor and outdoor units for 1 minute, then restore power.
Urgent
Fix now
Source
Rheem RP18AZ Installation Instructions high-pressure section and fault table