Marey tankless water heater shows E1 and shuts down; burner does not stay lit or never ignites.

Safety first: Turn OFF gas at the shutoff valve and switch OFF electrical power. Wait several minutes to clear any residual gas. Do not attempt repair if you smell strong gas—ventilate and call your gas supplier or emergency services.

Basic checks:

• Confirm gas supply: Ensure the gas shutoff valve to the Marey heater is fully open. Verify that other gas appliances (stove, furnace) are working normally.
• Check gas type and pressure: Confirm the heater is configured for the correct gas type (NG or LPG) and that the regulator is appropriate. If you suspect low pressure, a licensed gas technician must measure and adjust.
• Inspect burner area: Remove the front cover. Look for soot, rust flakes, or debris on the burner and around the igniter. Gently vacuum or brush loose debris without damaging components.
• Clean igniter and flame sensor: Locate the igniter/flame rod assembly near the burner. Lightly clean the ceramic and metal rod with fine emery cloth or a Scotch-Brite pad to remove oxidation. Do not bend the rod. Ensure the gap and position relative to the burner match the service manual.
• Check wiring: Inspect the igniter and flame sensor wires for loose connections or damage. Reseat connectors firmly.
• Test operation: Restore gas and power. Open a hot water tap and observe through the inspection window (if present). If the unit still shows E1, the igniter or flame sensor assembly may need replacement.

When to call a technician: Any gas pressure adjustment, burner removal, or if ignition components need replacement and you are not experienced with gas appliances.