Checking of A/C System For Pressure Leaks

Checking of A/C System for Pressure Leaks

After completing the evacuation, close manifold gauge high pressure valve and low pressure valve, and then wait 10 minutes. Verify that low pressure gauge reading has not changed.

CAUTION: If the gauge reading moves closer to "0", there is a leak somewhere. Inspect the tubing connections, make necessary repairs, and evacuate system once again, making sure that there are no leaks.

Procedure of Charging

CAUTION:
- Always charge through low pressure side of A/C system at after the initial charging is performed from the high pressure side with the engine stopped.
- Never charge to high pressure side of A/C system with engine running.
- Do not charge while compressor is hot.
- When installing tap valve to refrigerant container to make a hole, carefully follow directions given by manufacturer.
- A pressure gauge should always be used before and during charging.
- The refrigerant container should be emptied of refrigerant when discarding it.
- The refrigerant container should not be heated up to 40 °C (104 °F) or over.
- Refrigerant container should not be reversed in direction during charging. Reversing in direction causes liquid refrigerant to enter compressor, causing troubles, such as compression of liquid refrigerant and the like.

NOTE:
- The air conditioning system uses HFC-134a (R-134a).
- Described here is a method to charge the air conditioning system with refrigerant from the refrigerant service container.
- When charging refrigerant recovered by using the refrigerant and recycling equipment (when recycling refrigerant), follow the procedure described in the equipment manufacturer's instruction manual.

Charging procedure
Charge proper amount of refrigerant accurately in accordance with the following procedure.
Specified amount of refrigerant: 500 ± 30 g (17.65 ± 1.05 oz)

The initial charge of the A/C system is performed from the high pressure side with the engine stopped.




And next, this method must be followed by charging from the low pressure side with the engine running.
1. Check to make sure that hoses are routed properly after evacuating the system.
2. Connect Low charging hose (1) and High charging hose (2) of the manifold gauge set (3) in position. Thus, open refrigerant container valve (4) to purge the charging line.
3. Open the high pressure side valve (5) and charge refrigerant to system.
4. After a while, open the low pressure side valve (6) and close the high pressure side valve (5).

WARNING: Make sure that high pressure side valve is closed securely.

5. Start engine and keep engine speed at 1500 r/min. Then, operate air conditioning at "DEF" or "DEF/FOOT" air flow mode.
6. Charge A/C system with refrigerant. At this time, refrigerant container (4) should be held upright.
7. Remove manifold gauge set as follows:

WARNING: High pressure side is naturally under high pressure. So, care must be taken to protect your eyes and skin.

a. Close low pressure side valve of manifold gauge set. (The high pressure side valve is closed continuously during the process of charging.)
b. Close refrigerant container valve.
c. Stop engine.
d. Using shop rag, remove charging hoses from service valves. This operation must be performed rapidly.
e. Put caps on service valves.

Replacement of refrigerant container in charging procedure
When refrigerant container (1) is emptied, use the following procedure to replace it with a new refrigerant container (1).
1. Close low pressure valve.




2. Replace empty container (1) with a refrigerant container which has been charged with refrigerant. When using refrigerant container tap valve (2), use the following procedure for replacement.
a. Retract needle (3) and remove refrigerant container tap valve (2) by loosening its plate nut (4).
b. Install the refrigerant container tap valve (2) to a new refrigerant container (1).




3. Purge any air existing in center charging hose When using refrigerant container tap valve, use the following procedure to purge air.
a. Once fully tighten refrigerant container tap valve (1), and then loosen (open) plate nut (2) slightly.
b. Open low pressure side valve (3) of manifold gauge set (4) a little.
c. As soon as refrigerant comes out with a "hiss" through a clearance between refrigerant container and tap valve, tighten plate nut (2) as well as low pressure side valve (3).
d. Turn handle of tap valve (1) clockwise so that its needle is screwed into the new container to make a hole for refrigerant flow.