Boiler shows E15; may indicate condensate drain or trap fault on condensing models

Safety: Turn off power. Condensate is mildly acidic; wear gloves and eye protection.

• Locate condensate trap: On Crown condensing boilers, the trap is usually a plastic assembly at the bottom of the heat exchanger.
• Inspect drain line: Follow the plastic tubing from the trap to the drain. Look for kinks, sags filled with water, or freezing in unheated spaces. Straighten or thaw as needed.
• Clean trap: Place a container under the trap, disconnect it per the manual, and flush with clean water to remove debris. Reassemble, ensuring all seals are tight.
• Check float switch (if present): Some traps have an internal float switch. Make sure it moves freely and is not stuck by sludge.
• Reset: Restore power and reset the boiler. If E15 persists, have a technician inspect the condensate system and safety switches.