Pentair ERR IGN: Ignition Control Fault
ERR IGN shows up when a Pentair heater attempted to light the burner but its ignition control never detected a flame, so it locked itself out.
medium severityApplies to: Pentair MasterTemp and MiniMax NT residential gas pool/spa heaters
What it means
You hear the blower spin up, maybe a faint click or two from the ignition module, and then the burner never catches — after three attempts the display settles on ERR IGN and stays there. That's a hard lockout: the control board ran its normal sequence of purge, ignite, and prove-flame, and the flame-sensing circuit never saw what it needed to, so it stopped trying rather than keep sending gas into a chamber with nothing lit. The fault can originate almost anywhere along the ignition chain — the gas supply, the electrical side, or the sensor that watches for flame — which is exactly why the checks below stop at ruling out the obvious, low-risk causes before anyone opens the burner compartment.
Likely causes
- Gas supply valve closed, low gas pressure, or an empty propane tank
- Weak, cracked, or fouled hot-surface igniter
- Corroded or misaligned flame-sensing rod
- Failed ignition control module or gas valve
What you can check yourself
- Confirm the gas valve is fully open and, for propane, the tank has fuel
- Press HEATER OFF to clear the lockout and allow another attempt
- Check whether other gas appliances on the same line are operating normally
Do not attempt to service the igniter, flame sensor, or gas valve yourself. If the gas supply checks out but ignition keeps failing, shut the heater off and have a licensed technician inspect the ignition components.
Sources
Related reading
- All Pentair error codes
- Pentair ERR AFS — air flow switch open
- Pentair E01 — open water temperature sensor
- Symptom: Pool Heater Won't Ignite