Refrigerant Piping Work - Panasonic OCU-R200SF Service Manual

The quality of the design and construction work of refrigerant piping has great impact on the performance and reliability of Condensing unit. Observe precautions
given below in the case of design and construction work.
The compressor is cooled by liquid injection, if the refrigerant charge volume is not enough, the cooling effect will be decreased due to gas bubble in liquid line, it
will result in high temperature of compressor. Do not operate the unit under lack of refrigerant conditions.
The sizes of piping by unit models are given as below. However, note that an optimal size shall be decided by calculating the loss of pressure in piping and the
flow rates of a refrigerant so that cooling capacity and oil return would not be affected.
Model
Liquid Line
Suction Line
Do not contaminate the unit with dust, metallic powder, oxidized scale, etc.
Since the unit is composed of highly-precise components, any contaminants mingled into will damage the unit, with gas leakage,
capacity reduction, even abrasion and burn.
1.Spray with nitrogen gas during brazing (Strictly abide by).
2.Use the deoxidized phosphorus copper pipes that are clean both inside and outside.
3.When cutting or deburring a copper pipe, do not allow chips to contaminate the pipe. The customer should install the
suction filter on the suction line by themselves.
Air-tight Test（After piping construction work, before heat insulation work）
After the piping construction work, conduct the air-tight test as below:
Refrigerant
R22
R404A
1.Install and insulate the bulb according to the instruction. Make it sure minimum 5K superheat in all conditions.
Install angle of Bulb
Pipe diameter less than φ25.4(1 inch)：upper position
Pipe diameter more than φ25.4(1inch)：Lower postion 45° （4 o'clock position）
2.The superheat degree will become less in winter season, adjust the expansion valve to make sure minimum 5K
superheat degree.

Refrigerant Piping Work

Size of refrigerant piping
OCU-R Series, OCU-NR Series
3/8"（φ9.53）
5/8"（φ15.88）
High Pressure Side Low Pressure Side
2.8MPa
2.84MPa
Expansion valve
Metal Fixture
Page
1.4MPa
1.75MPa
The bulb package installation method is as shown in the
figure. The bulb needs to be installed horizontally.
15
Other Model
3/8"（φ9.53）
3/4"（φ19.05）
Insulation
Material
45°