SiEN34-705
Installation
General Information
25
Refrigerant Pipe
Flushing
[3 major effects]
1. Removal of oxidation bubbles formed inside copper pipes when “nitrogen replacement is
insufficient” during soldering work
2. Removal of extraneous material and moisture from pipes when covering has been
insufficient
3. Checks connections in pipes linking outdoor and indoor units (Both liquid and gas pipes)
[Example of procedure]
1. Set pressure regulator on nitrogen cylinder.
∗
The gas used must be nitrogen.
(There is a danger of condensation if fleon or carbon dioxide are used and oxygen carries
the risk of explosions.)
2. Connect the charge hose from the pressure regulator to the service port on the liquid pipe
side of the outdoor unit.
3. Fit blanking plugs to all indoor units (B) other than unit A.
4. Open the main valve on the nitrogen cylinder and set the pressure regulator to 0.5MPa.
5. Check that the nitrogen is passing through the unit A liquid pipe.
6. Flushing.
!
Block the end of the pipe with the insulation of your hand.
↓
!
When the gas pressure becomes too great to contain remove insulation quickly. (First flush)
↓
!
Block the end of the pipe with insulation again.
↓
(Carry out second flushing)
Flushing is a method of cleaning extraneous matter out of pipes using pressurized gas.
Pressure regulator
Outdoor unit
Gas pipe
Liquid pipe
Liquid pipe
Gas pipe
Blanking plug (brass)
Flare nut
Copper pipe
Pressure regulator
Nitrogen
Main valve
Primary
side
Secondary
side
0.5 MPa
Wood
Gas pressure of 0.5 MPa
Insulation
