Honda HR-V: A/C System Description - A/C Pressure Sensor

The A/C pressure sensor is attached to the receiver line on the outlet side of the A/C condenser. The sensor's output voltage changes in response to changes in A/C discharge pressure. The PCM receives the voltage signal and it is used to drive the A/C compressor. When the A/C system pressure rises to an upper limit, or decreases to a lower limit, PCM stops the A/C compressor to protect the system.

• Upper limit: 2, 850 kPa (29.06 kgf/cm2, 413.4 psi)
• Lower limit: 196 kPa (2.00 kgf/cm2, 28.4 psi)
• High speed fans switch point: 1, 600 kPa (16.32 kgf/cm2, 232.1 psi)

NOTE: This illustration is an example only. Appearance and structure of the actual parts may vary depending on the model.

A/C SYSTEM DESCRIPTION - COMPRESSOR

A/C Compressor

The A/C compressor is a pump that compresses refrigerant. It is driven by the engine accessory drive belt.

When the compressor clutch is OFF, the rotor pulley and armature plate are disconnected and the compressor does not operate. When the compressor clutch is ON, the field coil is energized, creating a strong magnetic field. This magnetic field locks the rotor pulley and armature plate together, driving the compressor. The compressed refrigerant becomes a high pressure and temperature vapor that is sent to the A/C condenser.

A/C compressor has a mechanical relief valve, and the valve opens when pressure exceeds the rated value. It cannot be reused, and should be replaced.

NOTE: This illustration is an example only. Appearance and structure of the actual parts may vary depending on the model.

A/C SYSTEM DESCRIPTION - CONDENSER

Sub Cool Cycle Condenser System

The condenser and receiver/dryer are integrated. The main A/C condenser changes the high pressure and temperature refrigerant vapor from the A/C compressor into a high pressure and temperature liquid. This allows the refrigerant to release heat to the outside air. The receiver/dryer acts as a reservoir of liquid refrigerant for the expansion valve. It also removes debris and moisture from the refrigerant. The sub A/C condenser cools the high pressure and temperature liquid refrigerant even further to improve A/C performance.

NOTE: This illustration is an example only. Appearance and structure of the actual parts may vary depending on the model.

A/C SYSTEM DESCRIPTION - EVAPORATOR TEMPERATURE SENSOR

The evaporator temperature sensor is a clip-type thermistor, with a sensing element that is directly mounted to the evaporator core fins. The sensor is connected to the climate control unit and constantly monitors the evaporator core's temperature. The A/C compressor and fans are cycled off briefly if the temperature approaches the freezing point of water. If the evaporator temperature goes too low, the moisture condensing on its cold surfaces will freeze, causing restricted evaporator airflow and poor A/C performance.

NOTE: This illustration is an example only. Appearance and structure of the actual parts may vary depending on the model.

A/C SYSTEM DESCRIPTION - OUTSIDE AIR TEMPERATURE SENSOR

The outside air temperature sensor is installed on the front side of the vehicle, behind the front bumper. The outside air temperature sensor uses a sensor that decreases resistance when temperature rises. The climate control unit or the HVAC control unit calculates the outside air temperature based on the information received from the outside air temperature sensor.

NOTE: This illustration is an example only. Appearance and structure of the actual parts may vary depending on the model.

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