Air conditioner

Abstract

An air conditioner includes: a compressor; an engine configured to drive the compressor; an exhaust gas reduction device including a catalyst an exhaust gas temperature sensor configured to detect an exhaust gas temperature of the engine; a coolant flow regulator configured to regulate a flow rate of a coolant supplied to the engine; an outdoor heat exchanger; an outdoor fan configured to blow air to the outdoor heat exchanger; and a controller configured to control the engine, the coolant flow regulator, and the outdoor fan, wherein the controller is configured to: control the engine to delay an ignition timing of the engine and control the coolant flow regulator to decrease the flow rate of the coolant, decrease a rotation speed of the outdoor fan to increase a pressure of the refrigerant, and control the engine to increase an RPM of the engine.

What is claimed is: 
     
         1 . An air conditioner, comprising:
 a compressor configured to compress a refrigerant;   an engine configured to use natural gas as fuel and drive the compressor;   an exhaust gas reduction device including a catalyst configured to react with exhaust gas generated by the engine;   an exhaust gas temperature sensor configured to detect an exhaust gas temperature of the engine;   a coolant flow regulator configured to regulate a flow rate of a coolant supplied to the engine;   an outdoor heat exchanger;   an outdoor fan configured to blow air to the outdoor heat exchanger; and   a controller, comprising circuitry, configured to control the engine, the coolant flow regulator, and the outdoor fan,   wherein the controller is configured to:   based on the exhaust gas temperature being lower than a reference temperature, control the engine to delay an ignition timing of the engine and increase a revolutions per minute (RPM) of the engine and control the coolant flow regulator to decrease the flow rate of the coolant.   
     
     
         2 . The air conditioner of  claim 1 , wherein the controller is further configured to: when the air conditioner operates in a cooling mode, control the outdoor fan to decrease a rotation speed of the outdoor fan based on the exhaust gas temperature being lower than the reference temperature 
     
     
         3 . The air conditioner of  claim 2 , further comprising: a compressor outlet pressure sensor configured to detect a pressure of the refrigerant compressed by the compressor,
 wherein the controller is configured to decrease the rotation speed of the outdoor fan such that the pressure of the refrigerant detected by the compressor outlet pressure sensor becomes equal to or higher than a reference pressure.   
     
     
         4 . The air conditioner of  claim 1 , wherein the controller is configured to: when the air conditioner operates in a cooling mode or a heating mode, control the engine to delay the ignition timing of the engine and increase the revolutions per minute (RPM) of the engine based on the exhaust gas temperature being lower than the reference temperature. 
     
     
         5 . The air conditioner of  claim 1 , wherein the controller is configured to: when the air conditioner operates in a cooling mode or a heating mode, control the coolant flow regulator to decrease the flow rate of the coolant based on the exhaust gas temperature being lower than the reference temperature.