6
e n
4 - 1 . P U R G I N G P R O C E D U R E S A N D L E A K T E S T
1) Remove service port cap of stop valve on the side of the outdoor unit gas pipe. (The
stop valves are fully closed and covered in caps in their initial state.)
2) Connect gauge manifold valve and vacuum pump to service port of stop valve on
the side of the outdoor unit gas pipe.
3) Run the vacuum pump. (Vacuumize for more than 15 minutes.)
4) Chec the vacuum ith gauge manifold valve, then close gauge manifold valve,
and stop the vacuum pump.
5) Leave as it is for one or t o minutes. Ma e sure the pointer of gauge manifold valve
remains in the same position. Confirm that pressure gauge sho s -14. psi Gauge
(-0.101 MPa).
6) Remove gauge manifold valve quic ly from service port of stop valve.
) After refrigerant pipes are connected and evacuated, fully open the valve stem of
all stop valves on both sides of gas pipe and liquid pipe by the hexagonal rench.
If the valve stem hits the stopper, do not turn it any further. Operating ithout fully
opening low ers the performance and this causes trouble.
8) Refer to 1-2., and charge the prescribed amount of refrigerant if needed. Be sure
to charge slow ly w ith liquid refrigerant. Otherw ise, composition of the refrigerant in
the system may be changed and affect performance of the air conditioner.
9) Tighten cap of service port to obtain the initial status.
10) Leak test
Gauge manifold
valve
(for R410A)
Compound pressure
gauge (for R410A)
Handle High
Charge hose
(for R410A)
Pressure gauge
(for R410A)
-14.7 psi
(-0.101 MPa)
Handle Low
Vacuum pump
(for R410A)
Stop valve cap
(Torque 15 to
20 ft-lb, 21.5 to
27.5 N•m, 220
to 280 kgf•cm)
Close
Open
Hexagonal w rench
Service port cap
(Torque 7 to 9 ft-lb,
10 to 12 N•m, 100
to 120 kgf•cm)
4 - 2 . G A S C H A R G E
Perform gas charge to unit.
1) Connect gas cylinder to the service port of stop valve.
2) Perform air purge of the pipe (or hose) coming from refrigerant gas cylinder.
3) Replenish specified amount of the refrigerant, hile operating the air conditioner for cooling.
N o t e :
In case of adding refrigerant, comply ith the quantity specified for the refrigerating cycle.
C A U T I O N :
When charging the refrigerant system w ith additional refrigerant, be sure to use liquid refrigerant.
Adding gas refrigerant may change the composition of the refrigerant in the system and affect
normal operation of the air conditioner. Also, charge the liquid refrigerant slow ly, otherw ise the
compressor w ill be locked.
To maintain the high pressure of the gas cylinder, w arm the gas cylinder w ith w arm w ater (under
104 (40 C)) during cold season. But never use na ed fire or steam.
Union
Stop valve
Liquid
pipe
Indoor
unit
Stop valve ith
service port
Gas
pipe
Refrigerant gas
cylinder
operating valve
(for R410A)
Gauge manifold
valve (for R410A)
Charge hose
(for R410A)
Refrigerant gas cylinder for R410A w ith siphon
Electronic scale for refrigerant charging
Refrigerant (liquid)
Outdoor
unit
Union
Union
Union
Model
Indoor unit
MXZ-2C
A
–
B
MXZ-3C
A
–
C
MXZ-5C
A
–
E
Stop valve cap
(Torque 18 to
22 ft-lb, 24.4 to
30.4 N•m, 250
to 310 kgf•cm)
Precautions w hen us-
ing the control valve
hen attaching the control valve
to the service port, valve core may
deform or loosen if excess pres-
sure is applied. This may cause
gas leak.
Service port
Charge hose
(for R410A)
Body
Close
Open
Control
valve
A
hen attaching the control valve to
the service port, ma e sure that the
valve core is in closed position, and
then tighten part A. Do not tighten
part A or turn the body hen valve
core is in open position.
4 . P U R G I N G P R O C E D U R E S , L E A K T E S T , A N D T E S T R U N
Valve stem
WARNING
W
h e n o p e n i n g o r c l o s i n g t h e v a l v e
b e l o w fre e zi n g t e m p e ra t u re s ,
re fri g e ra n t m a y s p u rt o u t fro m t h e
g a p b e t w e e n t h e v a l v e s t e m a n d t h e
v a l v e b o d y , re s u l t i n g i n i n j u ri e s .
Cap
Valve stem
Valve body
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