JPS6475848A - Air conditioner - Google Patents

Abstract

PURPOSE:To prevent the high pressure and the discharge pipe temperature from rising and indoor coils from being frosted thereby to improve the reliability of the air conditioner by identifying which load zone the operational condition corresponds to, allowing the air conditioner to perform a capacity control in accordance with the load in the case of the operational condition being a rated load zone, and at the time of overloading and at the time of space cooling, controlling the upper limit of the maximum operational frequency. CONSTITUTION:The air conditioner is provided with operational region identifying means 12 for receiving as input signals a room temperature signal from a room temperature detector 9, and an external air temperature detector 10 and identifying which these signals belong to of a space heating excessive load zone, a space cooling/heating rated load zone, a space cooling frosting load zone; and memory means 13 for storing in a readable manner respective maximum operational frequencies preset as ability limits in accordance with respective load zone sections. For example, when a case of operating the air conditioner under an overload condition in a space cooling period is considered, the operational region identifying means 12 identifies that it is one of the space cooling overload zones, and causes the memory means 13 to read out the maximum operational frequency corresponding thereto. Thereafter, frequency control means 14 actuates to limit of the operational frequency outputted by an inverter 11 to the maximum operational frequency.