Toshiba RAS-M18EACV-E, RAS-M13EKCVP-E, RAS-M14EACV-E, RAS-M16EKCVP-E, RAS-M10EKCVP-E Evacuating, 73

•Tightening torque for connection 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 the 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.

	Connectable capacity class
	A	B	Total
M14	10, 13	10, 13	23
M18	10, 13, 16*1	10, 13, 16*1	26

*1 When connecting a capacity class 16 pipe to the indoor unit, attach the expander which is available as an optional accessory to the 9.52 mm diameter packed valve of the outdoor unit.

φ6.35
φ9.52	Unit B
φ6.35
φ9.52	Unit A

Indoor unit

Outdoor unit

10-5-3. Evacuating

After the piping has been connected to the indoor unit, perform the air purge.

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 vacuum pump manual.

Use a vacuum pump

Be sure to use a vacuum pump with counter-flow prevention function so that oil inside the pump does not flow back into the air conditioner pipes when the pump stops. (If oil inside the vacuum pump enters into the air conditioner circuit which uses R410A, trouble with the refrigeration system may develop.)

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 the vacuum pump.

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

4.Operate the vacuum pump to begin 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). Confirm that the compound pressure gauge reading is –101 kPa (–76 cmHg).

5.Close the low pressure 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.

9.Perform steps 1 through 8 above on each connected indoor unit.

Compound pressure gauge	Pressure gauge
–101 kPa (–76 cmHg)	Manifold valve
Handle Lo	Handle Hi
Charge hose	(Keep full closed)
(For R410A only)	Charge hose
Connecting pipe	(For R410A only)
	Vacuum pump adapter for
	counter-flow prevention
	(For R410A only)

Vacuum pump

Packed valve at liquid side

Packed valve at gas side

Service port

(Valve core (Setting pin))

CAUTION

• IMPORTANT POINTS FOR PIPING WORK

(1)Keep dust and moisture from entering the pipes.

(2)Tighten connections carefully (between pipes and unit).

(3)Evacuate the air in the connecting pipes using a VACUUM PUMP.

(4)Check for gas leaks at all connections.

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