Install Instructions

2.2.5 Refrigerant pipe flushing
Flushing is a method of cleaning extraneous matter out of pipes using pressurized gas.
① Set pressure regulator on nitrogen cylinder.
② Connect the charge hose from pressure regulator to ser-
vice port on the liquid pipe side of the outdoor unit before
its connection to BD unit or indoor unit.
③ Open the main valve on the nitrogen cylinder and set the
pressure regulator to 0.5MPa(72.5psi)
④ Ensure that nitrogen is flowing through the pipe properly.
⑤ For flushing block the end of the pipe with wood insulation
block.
⑥ When the pressure becomes great remove the block
quickly.
⑦ Do step 6 & 7 repeatedly till cleanness is ensured.
⑧ Connect the charge hose from pressure regulator to ser-
vice port on the gas pipe side of outdoor unit before its
connection to BD unit or indoor unit.
⑨ Flow the steps 3, 4, 5, 6, 7.
⑩ In case of BD unit system, before connecting to indoor
units, each pipe should be flushed individually.
⑪ Flow the steps 3, 4, 5, 6, 7.
Refrigerant pipe flushing of 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)
NOTE
After welding the pipe, nitrogen flushing is strongly
recommended.
CAUTION
Gas pressure of 0.5MPa(72.5psi)
Taping
Primary
side
Pressure regulator
Nitrogen
Lo Hi
Secondary
side 0.5MPa(72.5psi)
Nitrogen
Lo Hi
Nitrogen
Lo Hi
Wood Insulation
2. Guideline for each installation process
Heat pump 60Hz/R410A _ 13
Installation of
Outdoor Units
SINGLE ZONE