Pentair Pool Heater & Pump Error Codes

Every documented Pentair fault code for MasterTemp and MiniMax NT heaters and IntelliFlo variable-speed pumps, what it means, and whether it's a DIY fix or a call for a technician.

Pentair's residential heaters — the MasterTemp and MiniMax NT lines — and its IntelliFlo family of variable-speed pumps both report faults as short on-screen text rather than blinking lights, which makes them more specific than older analog equipment, but only useful once you know what the text on the display actually means. Every code below has been checked against Pentair's own service documentation before being published here.

How to read the display

MasterTemp and MiniMax NT heaters show faults as a short string prefixed with "ERR" (like ERR PS or ERR AFS) or, for sensor faults, a plain code like E01. Some of these are soft faults that clear themselves once the underlying condition — low water flow, for instance — goes away on its own. Others, especially anything involving AGS or a tripped high-limit switch, are hard lockouts: the front panel disables itself and stays that way until the heater is power-cycled or, for a physically tripped limit switch, manually reset inside the cabinet. IntelliFlo pumps skip abbreviations and show plain-language alerts instead — "Priming Failure," "Overheat," "Over Current" — directly on the keypad, with the alert light staying lit and the buttons locked until the fault is cleared with the Reset button.

Pentair heater codes

Pentair pump codes

Not sure which code applies? Start from the symptom

If you haven't found the exact code yet, or the display is doing something these codes don't quite describe, these cross-brand symptom pages walk through the behavior itself.

• Pool Heater Won't Ignite
• Flow / Low-Flow Error
• Heater Runs But Pool Isn't Getting Warmer
• Pool Pump Won't Prime
• Heater or Pump Keeps Tripping the Breaker
• Communication Error Between Control and Display