Carrier XCT7 Installations- Und Benutzerhandbuch Seite 24

Installation procedure
• Weld the pipe and charge nitrogen simultaneously, or it will cause a
number of impurities (a film of oxidation) to clog the capillary and the
expansion valve, which may be fatal.
• Protect the pipe end from water and other impurities entering the
• Protect the pipe end from water and other impurities entering
the pipes flattening or being sealed with adhesive tape). pipes flattening or being sealed with adhesive tape).
Flat
Flat
Brazing
• The refrigerant pipe should be clean. The nitrogen should Brazing
flow under the pressure of about 0.2Mpa and when charging
nitrogen, shut off one end of the pipe by hand to enhance the
pressure in the pipe, then loosen and shut off the other end.
•When connecting the pipes, close the valves fully.
• When connecting the pipes, close the valves fully.
• When welding the valve and the pipes, use a wet cloth to cool down
• When welding the valve and the pipes, use a wet cloth to cool down the valve
the valve and pipes.
and pipes.
(1) Leakage tes t
1. The outdoor unit is tested for leakage in the factory. After connecting the distributing pipe, conduct
the leakage tes t from the outdoor check valve and the indoor unit. While testing, the valves should be
closed.
2. Refer to the figure below to charge nitrogen into the unit for testing. Never use chlorine, oxygen, or
other flammable gases for testing. Apply pressure on both the gas and liquid pipes.
3. Apply pressure step by step to achieve the target pressure.
a. Apply pressure on 0.5MPa for more than 5 minutes; check if pressure goes down.
b. Apply pressure on 1.5MPa for more than 5 minutes; check if pressure goes down.
c. Apply pressure on the target pressure (4.15MPa); record the temp. and pressure.
d. Leave it at 4.15MPa for over 1 day. If pressure does not go down, the test is successful. Note that,
when the temp. changes by 1 degree, pressure will
change by 0.01MPa as well. Correct the
pressure reading accordingly.
e. After confirmation of s teps a~d, if
pressure goes down, there is a leak.
Check the brazing position and flared
position by applying soapy water.
Correct any leaks found conduct another
leakage tes t.
4. After leakage tes t, perform evacuation.
(2) Evacuation
Evacuate at the check valve of the liquid s top valve and both sides of the gas s top valve. Operation
procedure:
Operation procedure:
Adhesive tape
Adhesive tape
Nitrogen
Nitrogen
After reaching-101KPa or
less (below-755mmHg),
Let the vacuum pump
continue running for at
least 1 hour.
If there is a loss of vacuum pressure, it shows there is moisture
or a leak in the system, correct any leaks and start the evacuation
process again
Taping
source valve
To indoor
To indoor
Gauge manifold
Gauge manifold
Lo
Lo
Lo handle
Lo handle
Leave it for over 1
hour, with no loss of
vacuum pressure
17
Seal the pipe end with
adhesive tape or the stopper
to increase resistance; fill up
the pipe with nitrogen.
<N2>
Only nitrogen Brazing
gas can be used
1st side 2nd side
0.2MPa
Hand
Check valve Check valve
Gas pipe
Gas pipe
Gas pipe
Gas pipe
Hi
Hi
Check hole
Check hole
Hi handle
Hi handle