7. Open the valve of the refrigerant cylinder, then open the charging valve slightly and close it. Next, press the check valve of the
manifold gauge and purge the air. (2)(4) (Watch the liquid refrigerant closely at this point.)
8. After adjusting the electronic scale to zero, open the charging valve, then open the valve Lo of the manifold gauge and charge
with the liquid refrigerant. (2)(5) (Be sure to read the operating instructions for the electronic scale.)
9. If you cannot charge the stipulated amount, operate the unit in the cooling mode while charging a little of the liquid at a time
(about 150 g/time as a guideline). If the charging amount is insufficient from one operation, wait about one minute, then use the
same procedure to do the liquid charging again.
Precaution:
Never use the gas side to allow a larger amount of liquid refrigerant to be charged while operating the unit.
10. Close the charging valve, and after charging the liquid refrigerant inside the charging hose, fully close the valve Lo of the
manifold gauge, and stop the operation of the unit. (2)(5)
11. Quickly remove the charging hose from the service port. (6) If you stop midway through, the refrigerant that is in the cycle will
be discharged.
12. After putting on the caps for the service port and operating valve, inspect around the caps for a gas leak. (6)(7)
Fig. 13 Re-charging refrigerant
9.4.6. Brazing
As brazing requires sophisticated techniques and experiences, it must be performed by a qualified person.
In order to prevent the oxide film from occurring in the pipe interior during brazing, it is effective to proceed with brazing while letting
dry nitrogen gas (N ) flow.
<Brazing Method for Preventing Oxidation>
1. Attach a reducing valve to the nitrogen gas cylinder.
2. Attach a reducing valve to the nitrogen gas cylinder.
3. Apply a seal onto the clearance between the piping and inserted pipe for the nitrogen gas in order to prevent the nitrogen gas
from flowing backward.
4. When the nitrogen gas is flowing, be sure to keep the piping end open.
5. Adjust the flow rate of nitrogen gas so that it is lower than 0.05 m /h, or 0.02 MPa (0.2 kgf/cm ) by means of the reducing valve.
33
CS-VC70KE / CU-VC70KE / CS-VC90KE / CU-VC90KE / CS-VC120KE / CU-VC120KE
Summary of Contents for CS-VC70KE
Page 4: ...2 Functions 2 1 REMOTE CONTROL 4 CS VC70KE CU VC70KE CS VC90KE CU VC90KE CS VC120KE CU VC120KE...
Page 5: ...2 2 INDOOR UNIT 5 CS VC70KE CU VC70KE CS VC90KE CU VC90KE CS VC120KE CU VC120KE...
Page 6: ...2 3 OUTDOOR UNIT 6 CS VC70KE CU VC70KE CS VC90KE CU VC90KE CS VC120KE CU VC120KE...
Page 48: ...13 Troubleshooting Guide 48 CS VC70KE CU VC70KE CS VC90KE CU VC90KE CS VC120KE CU VC120KE...
Page 52: ...52 CS VC70KE CU VC70KE CS VC90KE CU VC90KE CS VC120KE CU VC120KE...
