MTC-92
< SERVICE INFORMATION >
REFRIGERANT LINES
• If reusing the evaporator, install the thermo control amp. at the position marked when removing the
thermo control amp., if equipped (MR18DE - TYPE 2 systems).
• When recharging refrigerant, check for leaks.
Removal and Installation of Expansion ValveINFOID:0000000005930883
REMOVAL
1. Use the recovery/recycling equipment to evacuate the refrigerant.
2. Remove cowl top cover. Refer to EI-24, "
Removal and Installation".
3. Remove lower dash insulator.
4. Disconnect low-pressure flexible hose and high-pressure pipe from evaporator. Refer to MTC-59,
"Removal and Installation".
5. Remove expansion valve bolts (A), and then remove expansion valve (1).
CAUTION:
Cap or wrap the joint of the pi pe with suitable material such
as vinyl tape to avoid the entry of air.
INSTALLATION
Installation is in the reverse order of removal.
CAUTION:
• Replace O-rings of evaporator with new ones, and apply compressor oil when installing.
• When recharging refrigerant, check for leaks.
Checking of Refrigerant LeaksINFOID:0000000005930884
Perform a visual inspection of all refrigeration parts, fittings, hoses and components for signs of A/C oil leak-
age, damage and corrosion. A/C oil leakage may indicate an area of refrigerant leakage. Allow extra inspec-
tion time in these areas when using either an electronic refrigerant leak detector or fluorescent dye leak
detector.
If dye is observed, confirm the leak with an electronic refrigerant leak detector. It is possible a prior leak was
repaired and not properly cleaned.
When searching for leaks, do not stop when one leak is found but continue to check for additional leaks at all
system components and connections.
When searching for refrigerant leaks using an electronic leak detector, move the probe along the suspected
leak area at 25 to 50 mm (1 to 2 in) per second and no further than 1/4 inch from the component.
CAUTION:
Moving the electronic leak detector probe slower an d closer to the suspected leak area will improve
the chances of finding a leak.
Checking System for Leaks Using the Fluorescent Leak DetectorINFOID:0000000005930885
1. Check A/C system for leaks using the UV lamp and safety goggles J-42220 in a low sunlight area (area
without windows preferable). Illuminate all components, fittings and lines. The dye will appear as a bright
green/yellow area at the point of leakage. Fluoresce nt dye observed at the evaporator drain opening indi-
cates an evaporator core assembly (tubes, core or expansion valve) leak.
2. If the suspected area is difficult to see, use an adjustable mirror or wipe the area with a clean shop rag or cloth, with the UV lamp for dye residue.
3. After the leak is repaired, remove any residual dye using dye cleaner J-43872 to prevent future misdiag- nosis.
4. Perform a system performance chec k and verify the leak repair with an approved electronic refrigerant
leak detector.
NOTE:
SJIA0683E
Revision: May 2010 2011 Versa
MTC-94
< SERVICE INFORMATION >
REFRIGERANT LINES
2. When testing, circle each fitting completely with probe.
3. Move probe along component approximately 25 to 50 mm (1 to2 in) per second.
CHECKING PROCEDURE
To prevent inaccurate or false readings, make sure there is no refrigerant vapor, shop chemicals, or cigarette
smoke in the vicinity of the vehicle. Perform the leak test in calm area (low air/wind movement) so that the
leaking refrigerant is not dispersed.
1. Turn engine OFF.
2. Connect a suitable A/C manifold gauge set to the A/C service ports.
3. Check if the A/C refrigerant pressure is at least 345 kPa (3.45 bar, 3.52 kg/cm
2, 50 psi) above 16°C. If less
than specification, recover/evacuate and recharge the system with the specified amount of refrigerant.
NOTE:
At temperatures below 16 °C, leaks may not be detected since t he system may not reach 345 kPa (3.45
bar, 3.52 kg/cm
2, 50 psi).
4. Perform the leak test from the high-pressure side (compressor dischar ge a to evaporator inlet f) to the
low-pressure side (evaporator drain hose g to shaft seal k). Refer to MTC-76, "
Component". Perform a
leak check for the following areas carefully. Clean the component to be checked and move the leak
detected probe completely around the connection/component.
• Compressor Check the fitting of high- and low-pressure flexible hoses, relief valve and shaft seal.
• Condenser Check the fitting of high-pressure flexible hose and pipe, refrigerant pressure sensor.
• Liquid tank Check the refrigerant connection.
• Service valves
Check all around the service valves. Ensure service valve caps are secured on the service valves (to
prevent leaks).
NOTE:
After removing A/C manifold gauge set from service valves, wipe any residue from valves to prevent any
false readings by leak detector.
• Cooling unit (Evaporator)
With engine OFF, turn blower fan on “High” for at l east 15 seconds to dissipate any refrigerant trace in
the cooling unit. Wait a minimum of 10 minutes accumulation time (refer to the manufacturer’s recom-
mended procedure for actual wait time) before insert ing the leak detector probe into the drain hose.
Keep the probe inserted for at least 10 seconds. Use c aution not to contaminate the probe tip with water
or dirt that may be in the drain hose.
5. If a leak detector detects a leak, verify at least once by blowing compressed air into area of suspected
leak, then repeat check as outlined above.
SHA706E
SHA708EA
Revision: May 2010 2011 Versa
