Warning: Disconnect power before servicing.
ErrBase

Pentair Poolheater Error Codes

All Pentair poolheater error codes with step-by-step troubleshooting, multimeter specs, and OEM part numbers.

10 error codes

CodeMeaning
E05The pressure switch did not close during the heat cycle, indicating insufficient water flow or a failed switch.
highintermediate
ERR AFSThe combustion air flow switch (air pressure switch) did not close, indicating the combustion blower did not reach adequate speed or air flow is restricted.
highintermediate
ERR IGNThe heater attempted ignition multiple times and failed to establish or hold a flame, triggering a hard lockout.
highintermediate
ERR PSThe pressure switch fault code on IntelliFlo-integrated and newer digital-display Pentair models indicating insufficient water flow through the heater.
highintermediate
HUBReference guide covering all Pentair MasterTemp pool heater error codes and fault indicators.
lowbeginner
NO-POWERThe heater shows no display, no response to controls, or will not begin a heat cycle despite power appearing to be available.
moderatebeginner
NOT-HEATINGE05, E01, and Flow Switch Diagnosis
mediumintermediate
RESETProcedure for performing a soft reset, hard power reset, and service interval reset on Pentair MasterTemp pool heaters to clear fault codes.
lowbeginner
SERVICE-HEATERThe SERVICE HEATER indicator has illuminated, signaling either an annual maintenance interval has been reached or an active fault is present.
moderatebeginner
TROUBLESHOOTINGSymptom-based overview guide covering the six most frequent Pentair MasterTemp pool heater failures and how to diagnose each one.
moderatebeginner