Marey heater’s fan continues to run for a long time after hot water is turned off (gas model).

Safety first: None beyond normal; fan running is generally safe.

Steps:

• Determine if normal: Many gas tankless units run the fan for a short period after burner shutdown to clear flue gases. Check your Marey manual for expected duration.
• Observe duration: If the fan runs continuously for many minutes or never stops, turn off power and have the unit inspected.
• Check sensors and board (advanced): A technician can test the exhaust sensor and fan relay on the control board.

When to call a technician: If fan operation seems excessive or abnormal, or if it never shuts off.