Mitsubishi Electric MXZ-2HA40VF2 Manual De Instalación página 10

4. PURGING PROCEDURES, LEAK TEST, AND TEST RUN
4-1. PURGING PROCEDURES AND LEAK TEST
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 gas pipe side of the outdoor unit.
3) Run the vacuum pump. (Vacuumize for more than 15 minutes.)
4) Check the vacuum with gauge manifold valve, then close gauge
manifold valve, and stop the vacuum pump.
5) Leave as it is for one or two minutes. Make sure the pointer of gauge
manifold valve remains in the same position. Confirm that pressure
gauge shows -0.101 MPa [Gauge] (-760 mmHg).
6) Remove gauge manifold valve quickly from service port of stop valve.
7) 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 wrench. If the valve stem hits the stopper,
do not turn it any further. Operating without fully opening lowers the
performance and this causes trouble.
8) Refer to 1-2., and charge the prescribed amount of refrigerant if
needed. Be sure to charge slowly with liquid refrigerant. Otherwise,
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
To avoid risk of fire, make sure that there are no flammable
hazards or ignition risks before opening the stop valves.
WARNING
When opening or closing the valve
below freezing temperatures,
refrigerant may spurt out from the
gap between the valve stem and the
valve body, resulting in injuries.
4-2. GAS CHARGE
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, while operating the air
conditioner for cooling.
Note:
In case of adding refrigerant, comply with the quantity specified for the
refrigerating cycle.
When charging the refrigerant system with additional refrigerant, be
sure to use liquid refrigerant. Adding gas refrigerant may change the
composition of the refrigerant in the system and affect normal opera-
tion of the air conditioner. Also, charge the liquid refrigerant slowly,
otherwise the compressor will be locked.
To maintain the high pressure of the gas cylinder, warm the gas
cylinder with warm water (under 40°C) during cold season. But never
use naked fire or steam.
En-8
WARNING
Valve body
Valve stem
CAUTION
Close
Valve stem
Open
Hexagonal wrench
Service
port
Charge hose
Control
(for R32, R410A)
valve
Open
Close
A
Body
<R32>
Cap
Make sure to replace the
cap after the operation.
Union
Indoor
unit
Union
Indoor
unit
Refrigerant gas
cylinder operating
valve
(for R32, R410A)
Stop valve
Compound pressure
–0.101 MPa
for LIQUID gauge (for R32, R410A)
(–760 mmHg)
Pressure gauge
Stop valve cap (for R32, R410A)
(Torque 19.6 to
Gauge manifold
29.4 N•m, 200
valve (for R32,
to 300 kgf•cm)
R410A)
Handle
Handle High
Low
Charge hose (for
Stop valve
R32, R410A)
for GAS
Vacuum pump
Service port cap
(for R32, R410A)
(Torque 13.7 to 17.7
N•m, 140 to 180 kgf•cm)
Precautions when using
the control valve
When attaching the control valve
to the service port, valve core
may deform or loosen if excess
pressure is applied. This may
cause gas leak.
When attaching the control valve to
the service port, make sure that the
valve core is in closed position, and
then tighten part A. Do not tighten
part A or turn the body when valve
core is in open position.
Stop valve
Liquid pipe
Gas pipe
Outdoor
unit
Liquid pipe
Gas pipe
Service port
Gauge manifold
valve (for R32,
R410A)
Charge hose (for R32,
R410A)
Refrigerant gas cylinder for
R32, R410A with siphon
Refrigerant (liquid)
Electronic scale for
refrigerant charging