Toshiba RAS-22N3AV2-A, Руководство по обслуживанию

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CAUTION
<Tightening connection>
Align the centers of the connecting pipes and tighten
the flare nut as far as possible with your fingers. Then
tighten the nut with a spanner and torque wrench as
shown in the figure.
Outer dia. of copper pipe R410A
∅
6.35 1.5 to 2.0
∅
12.70
2.0 to 2.5
Imperial (wing nut type)
Half union Flare nut
Externally
threaded side
Internally
threaded side
Use a wrench
to secure.
Use a torque wrench
to secure.
Fig. 10-4-5
(Unit : N·m)
Outer dia.
Tightening torque
of copper pipe
¬ 6.35 14 to 18 (1.4 to 1.8 kgf·m)
¬ 12.70 50 to 62 (5.0 to 6.2 kgf·m)
.
CAUTION
 Do not apply excess torque.
 Otherwise, the nut may crack depending on the
conditions.
<Tightening orque of flare pipe connections>
The operating oressure of R410A is higher than that
of R22 (approx. 1.6 times). It is therefore necessary
to firmly tighten the flare pipe connecting sections
(which connect the indoor and outdoor units) up to the
specified tightening torque. Incorrect connections may
cause not only a gas leakage, but also damage to the
refrigeration cycle.
Fig. 10-4-6
Flare at indoor unit side
Flare at outdoor unit side
10-4-4. Evacuating
After the piping has been connected to the indoor unit,
you can perform the air purge together at once.
VACUUMING
Evacuate the air in the connecting pipes and in the
indoor unit using a vacuum pump. Do not use the
refrigerant in the outdoor unit.
For details, see the manual of the vacuum pump.
<Using 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.
1. Connect the charge hose from the manifold valve to
the service port of the packed valve at gas side.
2. Connect the charge hose to the port of the vacuum
pump.
3. Open fully the low pressure side handle of the
gauge manifold valve.
4. Operate the vacuum pump to start evacuating.
Perform evacuating for about 15 minutes if the piping
length is 20 meters. (15 minutes for 20 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 the
gauge manifold valve.
6. Open fully the valve stem of the packed valves
(both gas and liquid sides).
7. Remove the charging hose from the service port.
8. Securely tighten the caps on the packed valves.
Fig. 10-4-7
Packed valve at liquid side
Pressure gauge
Manifold valve
Packed valve at gas side
Vacuum pump
adapter for
counter-flow
prevention
-101 kPa (-76 cmHg)
Handle Lo
Compound pressure gauge
Charge hose
Connecting pipe
Vacuum
pump
Charge hose
Handle Hi
(Keep full closed)
Service port
(Valve core (Setting pin))
(If oil inside of the vacuum pump enters the air conditioner,
which use R410A, refrigeration cycle trouble may happen.)
(For R410A only)
(For R410A only)
(For R410A only)
FILE NO. SVM-13003
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