Toshiba RAS-10SAX Refrigerant Piping Connection, Vacuum Pumping, Flaring, Use of vacuum pump

8-5-1. Refrigerant Piping Connection

<Flaring>

(1) Cut the pipe with a pipe cutter.

90˚ Obliquity Roughness Warp

Fig. 8-5-2

(2) Insert a flare nut into the pipe, and flare the pipe.

		A	Outer	A (mm)
			diam.	Imperial Rigid
			6.35 mm 1.3 mm 0.7 mm
Die	Pipe		9.52 mm 1.6 mm 1.0 mm

Fig. 8-5-3

<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.

CAUTION

•Do not apply excess torque. Otherwise, the nut may crack depending on the installation conditions.

(Unit : N·m)

Outer diam.	Tightening torque	Additional
		tightening torque
6.35 mm	15.7 (1.6 kgf·m)	19.6 (2.0 kgf·m)
9.52 mm	29.4 (3.0 kgf·m)	34.3 (3.5 kgf·m)

8-5-2. Vacuum Pumping

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.

<Use of vacuum pump>

(1)Connect the charge hose (A) from the manifold valve to the charge inlet of the gas side packed valve.

(2)Connect the charge hose (B) to the port of vacuum pump.

(3)Open fully the low pressure side handle of the manifold valve.

(4)Operate the vacuum pump.

(5)Close the low pressure side handle of manifold valve after vacuumizing and stop the vacuum pump.

Continue vacuumizing more than 15 minutes and check the pressure gauge indicates –76 cmHg (–1.013×105Pa).

(6)Open the stems of packed valves A and B all the way.

(7)Securely tighten the stem cap to each of the packed valve stems.

	Manifold valve
Pressure gage	High pressure
	side handle
Low pressure side handle
Charge hose (A)	Lo Hi
Outdoor unit

Half union or packed valve	Flare nut
Externally	Internally
threaded	threaded
side	side
Use a wrench	Use a torque wrench
to secure.	to tighten.

Indoor unit		Gas
		(ø9.52)
	C		A
	D		B
		Liquid
		(ø6.35 )

Charge

hose (B)

Service port

VP

Packed valve

Fig. 8-5-4

Fig. 8-5-5

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