Boiler attempts to start but shuts down quickly with E02 displayed

Safety warning: Turn off power and gas before servicing. Flame loss can indicate combustion issues; if you smell gas, ventilate the area and contact a professional immediately.

• Check vent and air intake: For Crown condensing boilers with PVC venting, inspect the exhaust and intake pipes outside for blockages (ice, leaves, nests). Clear any obstructions.
• Inspect burner: Remove the burner cover and visually inspect the Crown premix burner for heavy dust, rust flakes, or debris. Lightly vacuum around the burner using a soft brush attachment. Do not damage burner mesh.
• Clean flame sensor: Remove and clean the flame sensor rod with fine abrasive pad as described in E01. Reinstall firmly.
• Check gas supply stability: If other gas appliances flicker or go out, there may be a supply issue. Contact your gas provider.
• Reset and test: Restore power and gas, reset the boiler, and observe operation. If E02 recurs, a technician should check combustion settings, manifold pressure, and the Crown control board.