Toshiba RAS-3M26GAV-E1, Руководство по обслуживанию

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• Tightening torque of flare pipe
The pressure of R410A is higher than R22.
(Approx. 1.6 times)
Therefore securely tighten the flare pipes which
connect the outdoor unit and indoor unit with the
specified tightening torque using a torque wrench.
If any flare pipe is incorrectly connected, it may
cause not only a gas leakage but also trouble in
the refrigeration cycle.
Fig. 10-4-9
Fig. 10-4-10
Half union
Flare nut
Externally
threaded side Internally
threaded side
Use a wrench to secure. Use a torque wrench to tighten.
Outdoor
unit
Indoor unit
D D UNIT
4M27 only
Ø6.35
Ø9.52
A A UNIT
Ø6.35
Ø12.7
C C UNIT
Ø6.35
Ø9.52
B B UNIT
Ø6.35
Ø9.52
Flare at
indoor
unit side
Flare at
outdoor
unit side
Fig. 10-4-11
Connectable capacity class
A B C D Total
10, 13 16 16
—
(with reducer) (with expander) (with expander)
45
16 10, 13 10, 13 —
10, 13 16 16 16
(with reducer) (with expander) (with expander) (with expander)
52
16 10, 13 10, 13 10, 13
3M26
4M27
10-4-7. Evacuating
After the piping has been connected to all indoor unit(s),
you can perform the air purge together at once.
AIR PURGE
Evacuate the air in the connecting pipes and in the
indoor unit using vacuum pump.
Do not use the refrigerant in the outdoor unit.
For details, see the manual of vacuum pump.
u
Use a vacuum pump
Be sure to use a vacuum pump with counter-flow
prevention function so that inside oil of the pump
does not flow backward into pipes of the air
conditioner when the pump stops.
(If inside oil of the vacuum pump enters into the
air conditioner which adopts R410A, a trouble of
the refrigeration cycle may be caused.)
1. Connect the charge hose from the manifold valve
to the service port of the gas side packed valve.
2. Connect the charge hose to the port of vacuum
pump.
3. Open fully the low pressure side handle of the
gauge manifold valve.
4. Operate the vacuum pump to start for evacuating.
Perform evacuating for about 35 minutes if the
piping length is total 70 meters. (25 minutes for
total 50 meters) (assuming a pump capacity of
27 liters per minute.)
Then confirm that the compound pressure gauge
reading is –101 kPa ( –76 cmHg).
5. Close the low pressure side valve handle of
gauge manifold.
6. Open fully the valve stem of the packed valves
(both sides of Gas and Liquid).
7. Remove the charging hose from the service port.
8. Securely tighten the caps on the packed valves.
Compound pressure gauge
Pressure gauge
Manifold valve
Handle Hi
(Keep full closed)
Charge hose
(For R410A only)
Vacuum pump adapter
for counter-flow prevention
(For R410A only)
Packed valve at gas side
Service port
(Valve core (Setting pin))
Handle Lo
Charge hose
(For R410A only)
–101kPa (–76cmHg)
Vacuum
pump
Packed valve
at liquid side
Fig. 10-4-12