| 摘要 |
<P>PROBLEM TO BE SOLVED: To solve a problem that water piping might freeze when a heat pump unit is not operated because information of outside air temperature can not be obtained if a power source of the heat pump unit is blocked at a hot-water storage tank unit side for reducing standby electricity. <P>SOLUTION: The outside air temperature is stored by a second electronic control device contained in a hot-water storage tank unit based on date information. After the power source to the heat pump is blocked, the outside air temperature is estimated, which blocks unnecessary power source to the heat pump unit and can reduce the standby electricity. <P>COPYRIGHT: (C)2009,JPO&INPIT |
