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Pentair pool heater error code

Pentair pool heater code ERR AGS / AGS: Automatic gas shutoff

Pentair MasterTemp heaters

What ERR AGS means

Automatic gas shutoff: water after the second pass through the heat exchanger is over 140°F. The buttons are disabled; you reset it by cycling power.

Also shown as: AGS, depending on the model.

Likely causes

  • Low water flow
  • Sensor or limit fault

Safe first checks

  1. Confirm full water flow (pump, baskets, filter, valves).
  2. Reset by turning the heater's power off and back on.

When to stop

If AGS repeats, call a qualified tech.

Checked against: Pentair MasterTemp heater installation and user's guide (Table 8: error and fault codes). Codes can differ by model and year, so confirm with your owner's manual.