The invention relates to a delayed protection method for an air conditioner. The method comprises the following steps: a, providing an indoor unit
discharge detection circuit, detecting an AD value of
residual voltage of an external
capacitor by using an indoor unit MCU (micro
control unit); b, sampling the AD value detected in the step a when the indoor unit MCU is powered on and comparing the AD value with records in a time-AD table one by one to obtain a power-
off time of an indoor unit; c, comparing the power-
off time of the indoor unit obtained in the step b with a startup interval time of an outdoor unit, wherein if the power-
off time of the indoor unit is greater than or equal to the startup interval time of the outdoor unit, the indoor unit immediately supply
electricity for the outdoor unit; and if the power-off time of the indoor unit is less than the startup interval time of the outdoor unit, the indoor unit can supply
electricity according to difference time between the power-off time of the indoor unit and the startup interval time of the outdoor unit. According to the air conditioner delayed protection method provided by the invention, the indoor unit can immediately supply
electricity to the outdoor unit when the power-off time of the outdoor unit exceeds a given value; when the power-off time of the outdoor unit is lower than the given value, an immediate power supply can be realized only by waiting for the difference time, thus the
waiting time of power supply can be shortened. By the adoption of the method, the
pressure balance of the air-conditioning
system can be protected well, and the air conditioner can perform refrigerating or heating rapidly.