Boiler shows E7 and shuts down; may indicate flue gas temperature too high.

Safety first: Turn off power and gas. High flue temperatures can indicate unsafe operating conditions and risk of heat damage or fire.

• Step 1 – Inspect vent system: Check the entire vent run for sags, disconnections, or restrictions. Ensure vent length and fittings comply with Bradford White installation requirements. Clear any obstructions at terminations.
• Step 2 – Check flue temperature sensor: Locate the flue gas temperature sensor on the exhaust outlet. Verify it is firmly attached and its wiring is intact. Replace the sensor if it is loose, damaged, or reading incorrectly (requires meter and chart).
• Step 3 – Verify combustion air: Ensure the combustion air intake is not blocked and that the boiler room has adequate ventilation if using room air.
• Step 4 – Burner input and gas pressure (pro only): A licensed technician should verify that the gas valve is properly adjusted and that the boiler is not overfired. Overfiring can cause excessive flue temperatures.
• Step 5 – Check for scale in heat exchanger: If the boiler is older or used with hard water (for combi/indirect applications), internal scale can reduce heat transfer and raise flue temperatures. Descaling should be performed by a professional.

Warning: Do not ignore repeated E7 codes; prolonged high flue temperatures can damage venting and create a fire hazard.