4
GB
2.2 Procedures for refrigerant oil recovery
1
Evacuating the existing pipes, and ensuring air tightness
Charge airtight gas through the service port on both the high-pressure and low-pressure valves. The air tightness should be
4.15 MPa. After checking the air tightness, evacuate the air through the service port on both the high-pressure and low-pressure valves.
2
Refrigerant charging
•If the length or diameter of the refrigerant pipe is unknown
Charge the required amount of refrigerant (indoor units + BC controllers) through both high-pressure and low-pressure service port valves.
•When refrigerant pipe diameter and length are already known
Charge the required amount of refrigerant (indoor units + BC contr pipes) through both the high-pressure and low-pressure service port
valves. See the table below for the required amount of refrigerant for the indoor units and BC controllers. To calculate the required amount of
refrigerant charged for the pipes, refer to 10.1. “Calculation of additional refrigerant charge” in the installation manual on the CD-ROM.
If there is excess refrigerant that cannot be charged, use it during oil recovery operation at step 4 (cooling operation).
* After charging the required amount of refrigerant to the existing pipes, open the valve so that the pressure in the existing pipes and outdoor unit
are equal. (Refer to Procedure 3.) Do not open the valve on the outdoor unit when the existing pipes are under vacuum. Doing so may cause
the refrigerant that is dissolved in the refrigerant oil in the compressor to form and cause some oil to migrate to the existing pipes, resulting in
insufficient lubrication.
Procedure 1
High-pressure valve
Low-pressure valve
Procedure 2
High-pressure valve
Low-pressure valve
Total capacity of
connected indoor units
Charged amount (kg)
- 80
2.0
81 - 160
2.5
161 - 330
3.0
331 - 390
3.5
391 - 480
4.5
Total outdoor unit Model
Charged amount per
BC controller
(Standard / Main) (kg)
P200
2.0
P250
3.0
P300
WT06218X01_en.fm Page 4 Tuesday, December 14, 2010 4:19 PM
