Pentair Pool Heater ERR AGS Error Code

What ERR AGS means

Automatic Gas Shutoff The automatic gas safety shutoff device has tripped. This is a critical safety lockout that prevents gas from reaching the burner. Control board fault triggering the AGS, gas valve wiring fault, AGS device internal failure, power interruption during operation. Do not attempt to bypass or jumper the AGS. Reset by power-cycling the heater. If AGS trips again without an obvious cause, a licensed technician must diagnose the control board and gas valve wiring before the heater is returned to service.

First checks before service

This page currently documents the safe reset triage. If the code returns, use the linked source manual or a qualified technician for code-specific diagnosis.

1. 1. One-time fault event (power disturbance or transient sensor reading) common DIY

   Check: Power-cycle at the breaker/disconnect (or unplug for CPAP), restore, and run the system while watching for the code.

   Fix: If the code does not return after a full run cycle, the fault was transient — monitor, no repair needed.

2. 2. Fault persists after a clean reset occasional pro only

   Check: If the code returns immediately or every session, note the conditions (startup, heating, after rain).

   Fix: A persisting code points at the component the manual assigns to this code — that repair is technician territory.