Water heating apparatus

A water heating apparatus, comprising:

• a burner;
• a heat exchanger for heating hot and cold water with use of heat from said burner;
• a sensor for detecting a flow rate in said heat exchanger;
• and
• a controller having a scale detector for detecting occurrence of scale clogging in said heat exchanger based on a temperature of said heat exchanger,
• said controller being configured to allow a display unit to output an error when an integrated value of a combustion time of said burner exhibits a predetermined value and scale clogging is detected by said scale detector, and
• said controller being configured to prohibit combustion operation of said burner when a time during which a predetermined flow rate is not detected by said sensor continues for a first time period after said error is outputted or when a second time period elapses after scale clogging is detected.

A water heating apparatus, comprising:

• a burner;
• a heat exchanger for heating hot and cold water with use of heat from said burner;
• a sensor for detecting a flow rate in said heat exchanger;
• an operation receiving unit for receiving user operation;
• and
• a controller having a scale detector for detecting occurrence of scale clogging in said heat exchanger based on a temperature of said heat exchanger,
• said controller being configured to allow a display unit to output an error and thereafter prohibit combustion operation of said burner when scale clogging is detected by said scale detector, and
• said controller being configured to cancel prohibition of the combustion operation of said burner for a predetermined time period when said operation receiving unit receives predetermined operation after the combustion operation of said burner is prohibited.