| 摘要 |
A water heater includes: a burner; a heat exchanger; a fan for supplying air to the burner and emitting combustion gas having passed through the heat exchanger to outside of the water heater; and a drainage water discharge path connected to the heat exchanger. The drainage water discharge path has a water-sealing structure that is water-sealed by drainage water. The water heater further includes a control unit: having a water-seal determination unit giving permission that the water heater can operate in a normal mode based on a condition that the drainage water discharge path has been water-sealed; and issuing an instruction to cause the burner to intermittently operate for a time period until the water-seal determination unit gives the permission. |
