Panasonic CU-5E34NBE Manual Del Usuario página 55

4. Air Purging
Air and moisture remaining in the refrigerant system
have undesirable effects as indicated below.
Therefore, they must be purged completely.
pressure in the system rises
�
operating current rises
�
cooling efficiency drops
�
moisture in the air may freeze and block capillary
�
tubing
water may lead to corrosion of parts in the
�
refrigerant system
Air Purging with a Vacuum Pump
�
(for Test Run)
In order to protect the earth's environment, be sure to
�
use a vacuum pump to perform the air purge.
(Never perform an air purge by using the refrigerant
gas cylinder or other external gas, or by using the gas
inside the outdoor unit.)
Perform the air purge for tubes A, B, C, D and E. Use
the same procedures for all tubes.
In order to prevent charging errors with the
CAUTION
air conditioner that uses R410A, the screw
diameter at the service valve charging port
has been changed. When recharging or
performing other servicing, use the special
charging hose and manifold gauge.
(1) Check that each tube (both narrow and wide
tubes) between the indoor and outdoor units have
been properly connected and all wiring for the test
run has been completed. Note that both narrow
and wide tube service valves on the outdoor unit
are kept closed at this stage.
(2) Using an adjustable wrench or box wrench,
remove the valve caps from the service valve on
both narrow and wide tubes.
(3) Connect a vacuum pump and a manifold valve
(with pressure gauges) to the service port on the
wide tube service valve. (Fig. 20).
Before using the vacuum pump
CAUTION
adapter, read the vacuum pump
adapter manual, and use the
adapter correctly.
Be sure to use a manifold valve
CAUTION
for air purging. If it is not
available, use a stop valve for
this purpose. The "Hi" knob of
the manifold valve must always
be kept closed.
Service
E
valve on
D
narrow
tube side
C
Service
B
valve on
wide tube
A
side
Hex wrench
(nominal size 4mm,
not provided)
With push-pin
Spindle
Screw diameter: 1/2"
UNF 20 threads
Valve core
Cap nut tightening torque:
8 – 10 N·m
(80 – 100 kgf·cm)
(Tighten by hand, then use a
wrench to turn approximately 30 .)
<Structure of service valve on wide tube side>
When using a hex wrench to open the spindle, an
�
extremely small amount of refrigerant may leak.
This does not indicate a problem.
Use a hex wrench of a type to which force can be
�
easily applied.
13
Manifold gauge
(special for R410A)
High-pressure valve
Low-pressure
Vacuum pump
valve
adapter
(for preventing
Leave the
Lo Hi
reverse flow)
valve open.
(special for
Open
R410A)
Charging hose
(special for R410A)
Fig. 20
Cap tightening torque:
3/8" 19 – 21 N·m
(190 – 210 kgf·cm)
Stopper
1/2" 24 – 26 N·m
(240 – 260 kgf·cm)
(Tighten by hand, then
use a wrench to turn
approximately 45°.)
Fig. 21
Vacuum
pump