Nissan Tiida C11. Manual - part 825

PREPARATION

HA-15

< PREPARATION >

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(Kent-Moore No.)
Tool name

Description

(J-41810-NI)
Refrigerant identifier equipment (R-
134a)

For checking refrigerant purity and 
system contamination

Power tool

Loosening bolts and nuts

RJIA0197E

PBIC0190E

HA-16

< FUNCTION DIAGNOSIS >

REFRIGERATION SYSTEM

FUNCTION DIAGNOSIS

REFRIGERATION SYSTEM

Refrigerant Cycle

INFOID:0000000001396439

REFRIGERANT FLOW

The refrigerant flows in the standard pattern, that is, through the compressor, the condenser with liquid tank,
through the evaporator, and back to the compressor. The refrigerant evaporation through the evaporator is
controlled by an externally equalized expansion valve, located inside the evaporator case.

FREEZE PROTECTION

Under usual operating conditions, when the A/C is switched ON, the compressor runs continuously, and the
evaporator pressure, and temperature is controlled by the compressor to prevent freeze up.

Refrigerant System Protection

INFOID:0000000001396440

REFRIGERANT PRESSURE SENSOR

The refrigerant system is protected against excessively high or low pressures by the refrigerant pressure sen-
sor, located on the condenser. If the system pressure rises above, or falls below the specifications, the refrig-
erant pressure sensor detects the pressure inside the refrigerant line and sends the voltage signal to the ECM.
ECM makes the A/C relay go OFF and stops the compressor when pressure on the high-pressure side
detected by refrigerant pressure sensor is over about 2,746 kPa (27.46 bar, 28.0 kg/cm

2

 , 398 psi), or below

about 134 kPa (1.34 bar, 1.4 kg/cm

2

 , 20 psi).

PRESSURE RELIEF VALVE

The refrigerant system is also protected by a pressure relief valve, located in the rear head of the compressor.
When the pressure of refrigerant in the system increases to an unusual level [more than 3.8 MPa (38 bar,
38.76 kg/cm

2

 , 551 psi)], the release port on the pressure relief valve automatically opens and releases refrig-

erant into the atmosphere.

1.

Compressor

2.

Pressure relief valve

3.

Liquid tank

4.

Refrigerant pressure sensor

5.

Condenser

6.

Expansion valve

AWIIA0054ZZ

REFRIGERATION SYSTEM

HA-17

< FUNCTION DIAGNOSIS >

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7.

Evaporator

8.

Blower motor

A.

High-pressure gas

B.

High-pressure liquid

C.

Low-pressure liquid

D.

Low-pressure gas

E.

Suction port

F.

Discharge port

G.

Outside air

HA-18

< FUNCTION DIAGNOSIS >

OIL

OIL

Maintenance of Oil Quantity in Compressor

INFOID:0000000001396442

The oil in the compressor circulates through the system with the refrigerant. Add oil to compressor when
replacing any component or after a large refrigerant leakage occurred. It is important to maintain the specified
amount.
If oil quantity is not maintained properly, the following malfunctions may result:
• Lack of oil: May lead to a seized compressor.
• Excessive oil: Inadequate cooling (thermal exchange interference)

OIL

MR18DE and HR16DE

: NISSAN A/C System Oil Type R

K9K

: NISSAN A/C System Oil Type S