| 摘要 |
An air conditioning system including a furnace (14) and a heat pump (18) selectively operable to provide relatively warm air to an enclosure. An indoor thermostat (46) having first and second threshold temperature settings senses the temperature of the air in the enclosure. A control coordinates the operation of the heat pump (18) and furnace (14) in response to the sensed temperature of the air in the enclosure. The control is operable in a first state to selectively activate the heat pump (18) whenever the first threshold temperature exceeds the sensed temperature and is operable in a second state to solely activate the furnace (14) whenever the second threshold temperature exceeds the sensed temperature. Whenever the furnace (14) is activated, the furnace (14) is maintained active and the heat pump inactive until the sensed temperature exceeds the first threshold temperature. |
