19
1. The stop valves for the gas pipe and liquid pipe on the indoor unit side are open, and those
on the outdoor unit side are closed.
2. (Leakage test with nitrogen) Inject nitrogen until the pressure reaches 3.0 MPa. Verify that
the pressure does not decrease after 24 hours under a stable ambient temperature. If any
leak is found after pressure preservation, check the pipe for leaks, especially the welding
points and stop valves.
3. (Vacuumizing) Replace the reducing valve and nitrogen cylinder with a vacuum pump.
Perform vacuumizing for at least 80 minutes and ensure that the final absolute pressure is
not greater than 60 Pa. When the final pressure does not decrease any more, continue to
vacuumize for 10 minutes. After vacuumizing is complete, close the vacuum pump and all
valves, and preserve the pressure for 10 minutes. Ensure that the absolute pressure does not
exceed 90 Pa. If the minimum reading of the pressure gauge is greater than 60 Pa, ensure
that the pointer stays at the smallest scale of the pressure gauge and preserve the pressure
for 1 hour. Then check that the pressure does not rise.
4. Open the stop valves for the gas pipe and liquid pipe of the outdoor unit.
9
Leakage Test with Nitrogen and Vacuumizing
•
After the outdoor unit stop valve is opened, the refrigerant in the outdoor unit flows to
the engineering pipe and indoor unit pipe. When performing other operations, be careful
to prevent refrigerant from spraying out.
•
After the vacuumization and before removing the rubber hose, ensure that there is
positive pressure inside the refrigerant pipe of the indoor unit. For detailed operations,
see step 1–4 in section "Commissioning Procedure".
Item
Check That
Check Result
Indoor fan The fan is secured. The fan has no foreign matter inside.
□
Passed
□
Failed
Wet film
humidifier
(optional)
The water inlet solenoid valve, humidifier water pump, and wet film
are secured.
□
Passed
□
Failed
Humidifier
float
The humidifier float is secured. The fasteners for the humidifier float
are secured.
□
Passed
□
Failed
Liquid level
detector
The liquid level detector is secured. The fasteners for the liquid level
detector are secured. The low liquid level detector functions flexibly.
□
Passed
□
Failed
Return air
filter
The arrow direction of the return air filter is consistent with the return
air direction.
□
Passed
□
Failed
Outdoor
unit
The outdoor unit is secured. The outdoor unit air intake and exhaust
vents are not blocked. The outdoor unit installation meets
requirements.
□
Passed
□
Failed
Pipe
Pipe connectors are correct. The refrigerant pipe tilts and has supports.
The hose clamps and cable ties of the drainpipe are secured. The
refrigerant pipe and water pipe are wrapped with thermal insulation
foam. All pipes have been checked for leaks. Water pipe joints have
been sealed by sealant. The water inlet pipe and drainpipe also have
been checked for leaks. All pipes are not bent by a large angle.
□
Passed
□
Failed
Cable
The input voltage is within the range of rated voltage
±
10%, and the
input frequency is within the range of rated frequency
±
3 Hz. Cables
are not damaged. All cables, connectors, and bolts are secured. All
devices are correctly grounded.
□
Passed
□
Failed
Summary of Contents for NetCol5000-A011
Page 14: ...13 Downward pipe routing ...
