Refrigerant Piping Connection; Evacuating; Wiring Connection; Tightening Connection - Toshiba Indoor unit RAS-18, 24SK Series Installation Manual

Refrigerant Piping Connection

Flaring
1. Cut the pipe with a pipe cutter.
90
. Insert a fl are nut into the pipe and fl are the pipe.
Projection margin in flaring : A (Unit : mm)
•
Outer dia.
A
of copper pipe
∅6.35
Die
Pipe ∅1.70
∅15.88

Tightening connection

Align the centers of the connecting pipes and tighten the fl are nut as far as
possible with your fi ngers. Then tighten the nut with a spanner and torque
wrench as shown in the fi gure.
CAUTION CAUTION
Do not apply excess torque. Otherwise, the nut may crack depending on
the conditions.
Outer dia. of copper pipe
∅6.35 mm
∅1.70 mm
∅15.88 mm
Tightening torque of flare pipe connections
•
Flare at
outdoor unit side
Half union
Externally
threaded side
Use a wrench to secure. Use a torque wrench to tighten.
CAUTION CAUTION
KEEP IMPORTANT 5 POINTS FOR PIPING WORK.
•
(1) Take away dust and moisture (inside of the connecting pipes).
() Tighten the connections (between pipes and unit).
(3) Evacuate the air in the connecting pipes using a VACUUM PUMP.
(4) Check gas leak (connected points).
(5) Be sure to fully open the packed valves before operation.

Evacuating

After the piping has been connected to the indoor unit, you can perform the
air purge together at once.
AIR PURGE
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-fl ow prevention function so
that inside oil of the pump does not fl ow backward into pipes of the air
conditioner when the pump stops.
Obliquity Roughness Warp
A
Rigid Imperial
1.0 to 1.5 1.5 to .0
1.0 to 1.5 .0 to .5
1.0 to 1.5 .0 to .5
(Unit : N·m)
Tightening torque
16 to 18 (1.6 to 1.8 kgf·m)
50 to 6 (5.0 to 6. kgf·m)
65 to 80 (6.5 to 8.0 kgf·m)
Flare at
indoor unit side
Flare nut
Internally
threaded side
1. Connect the charge hose from the manifold valve to the service port of
the packed valve at gas side.
. 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 0 meters. (15 minutes for 0
meters) (assuming a pump capacity of 7 liters per minute) Then confi rm
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.
Compound pressure gauge
–101 kPa
(–76 cmHg)
Handle Lo
Charge hose
Connecting pipe
Packed valve at liquid side
TO CHARGE REFRIGERANT
Refrigerant
Non refrigerant charging
Refrigerant charging
Packed valve handling precautions
Open the valve stem until it touches the stopper. Once it is in contact with
•
the stopper, refrain from applying any more force than is necessary.
Securely tighten the valve stem cap with torque in the following table:
•
Pipe side Tightening torque
Gas side 65 to 80 N·m
(∅15.88 mm) (6.5 to 8.0 kgf·m)
Gas side 50 to 6 N·m
(∅1.70 mm) (5.0 to 6. kgf·m)
Liquid side 16 to 18 N·m
(∅6.35 mm) (1.6 to 1.8 kgf·m)
9 to 10 N·m
Service port
(0.9 to 1.0 kgf·m)

Wiring Connection

1. Remove the valve cover, the electric parts cover and the cord clamp from
the outdoor unit.
. Connect the connecting cable to the terminal as identifi ed by the matching
numbers on the terminal block of indoor and outdoor unit.
3. Insert the power cord and the connecting cable carefully into the terminal
block and secure it tightly with screws.
4. Use vinyl tape, etc. to insulate the cords which are not to be used.
Locate them so that they do not touch any electrical or metal parts.
5. Secure the power cord and the connecting cable with the cord clamp.
6. Attach the electric parts cover and the valve cover on the outdoor unit.

Electrical Work

1. The supply voltage must be the same as the rated voltage of the air
conditioner.
. Prepare the power source for exclusive use with the air conditioner.
6
Pressure gauge
Manifold valve
Handle Hi
(Keep full closed)
Charge hose
Vacuum pump adapter for
counter-fl ow prevention
Vacuum
pump
Packed valve at gas side
Service port (Valve core (Setting pin))
18 Class 24 Class
Less than 15 m Less than 15 m
15 – 0 m (0g/m) 15 – 5 m (30g/m)
A
Hexagon wrench
is required.
5 mm
4 mm
Same as
gas side
Toshiba 1110651160 (EN)