Pentair Pool Heater ERR AGS Error Code
Quick answer
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
Severity: high · DIY difficulty: intermediate
Safety
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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.
Causes, ranked
1. Automatic Gas Shutoff device tripped by overheat condition occasional pro-only
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Fix:
2. Failed AGS switch occasional pro-only
Check:
Fix:
Parts & supplies for Pentair Pool Heater: filters, control boards, sensors, and common replacement parts.
Sources
- PoolDial error-code reference (manual-backed) — verified 2026-08-29
- Pentair MasterTemp/Max-E-Therm Heater Installation & User's Guide (Section 5 Troubleshooting) — verified 2026-08-29