Toshiba MMU-AP0091H service manual Check list, Additional amount of refrigerant by pipe length

3. Connection check between Flow Selector Unit (FS Unit) and indoor unit

Check list 2

1			Remote
	Indoor unit
			controller
		A	A
U1/U2		B	B
	Earth terminal	Control	FS unit
		wiring
	CN81		CN02
L	N	Power	CN01
		line
3			Earth
	Earth terminal		terminal

Power supply Single phase 220-240V, 50Hz

Earth leakage	Pull	2
breaker	Box
Power switch

Indoor unit		Remote
		controller
	A	A
U1/U2	B	B
Earth terminal	Control	FS unit
	wiring
CN81		CN02
L N	Power	CN01
	line
		Earth
Earth terminal		terminal
Pull		4
Box

Indoor unit		Remote
		controller
	A	A
U1/U2	B	B
Earth terminal	Control	FS unit
	wiring
CN81		CN02
L N	Power	CN01
	line
		Earth
Earth terminal		terminal

Calculate the additional amount of refrigerant from the following:
Additional amount		Actual liquid	Additional amount of	× 1.3		Corrective amount of
of refrigerant (B)	=	pipe length ×	refrigerant per liquid pipe 1m		+	refrigerant by system capacity
		                   				             
			(A)			(B)

Firstly enter the total length for each liquid pipe in the following table and then calculate the additional amount of refrigerant by pipe length.

Additional amount of refrigerant by pipe length

Pipe dia at	Standard amount of refrigerant	Total pipe length at each liquid side	Additional amount of refrigerant pipe
liquid side	kg/m		dia at each liquid side	kg
Ø 6.4	0.025 ×	=		kg
Ø 9.5	0.055 ×	=		kg
Ø 12.7	0.105 ×	=		kg

87

No. Main check items Check

•Are indoor/outdoor communication lines connected to U1/U2 terminals?

‚Is the signal line of the FS unit connected to connector CN81?

ƒIs the power supply cable of the FS unit connected to R (L) and S (N) terminals?

„Is the power supply cable of the FS unit connected to the closed end connector?

When the indoor unit is a Wall type (1 Series) or Concealed Duct High Static Pressure type?

Note) The above figure does not cover all the electric wirings.

For details, refer to the Installation Manual of Flow selector unit.

Check list 1

• Using the “Check list 1”, check there is no trouble in the installation work.

Is capacity of the leak	Outdoor total capacity	XXXX	A	Header unit (A)	XXXX	A	Indoor unit	XXXX		A
breaker appropriate?				Follower unit (B)		A
					XXXX
				Follower unit (C)	XXXX	A
Is the diameter of the power cable correctly wired?				Header unit (A)		mm²	Indoor unit			mm²
					XXXX			XXXX
				Follower unit (B)	XXXX	mm²
				Follower unit (C)	XXXX	mm²
Is the control communication line correctly wired?				Indoor –outdoor connection terminals (U1, U2)
									XXXX
				Outdoor–outdoor connection terminals (U5, U6)					XXXX
				Central control system connection terminals (U3, U4)					XXXX
Is the power of the indoor units supplied collectively?
Is the earth grounded
Is the insulation good? (10MΩ or more)						MΩ or more
					XXXX
Is the main power voltage correct? (Within 200V ± 10%)						V
					XXXX

Is the diameter of the connecting pipe correct?

Is the branch kit correct?

Does the indoor unit condensate drain adequately?

Is the thermal insulation of pipes good? (Connecting pipes, Branch kit)

For both indoor and outdoor units, ensure air is not short-circuited from discharge to inlet ports.

After pressure test, check that the pipework and indoor units have been vacuumed and the correct amount of additional gas has been charged.

Are valves of all the outdoor units fully opened?	Suction gas side		Discharge gas side		Liquid side		Balance side
Header unit (A)		XXXX		XXXX		XXXX		XXXX
Follower unit (B)		XXXX		XXXX		XXXX		XXXX
Follower unit (C)		XXXX		XXXX		XXXX		XXXX

• Check the additional amount of refrigerant.

Ø 15.9	0.160 ×	=	kg
Ø 19.0	0.250 ×	=	kg
Ø 22.2	0.350 ×	=	kg
		Additional amount of refrigerant by pipe	kg
		length (A)

Next, refer to the following table for the corrective amount of refrigerant (B) by system capacity.

Corrective amount of refrigerant by system capacity

			Normal type
System horse power HP
	Unit 1	Unit 2	Unit 3	Corrective amount of refrigerant (B) kg
8	8			2.0
10	10			2.5
12	12			3.0
16	8	8		–1.5
18	10	8		0
20	10	10		2.0
24	8	8	8	–4.5
26	10	8	8	–3.0
28	10	10	8	–1.5
30	10	10	10	0

Finally add the additional amount of refrigerant by pipe length (A) to the corrective amount of refrigerant by system capacity (B). This is the final additional amount of refrigerant.

If the result is indicated as a negative, do not add any refrigerant. Do not add the refrigerant (= 0kg).

Additional amount of refrigerant

Additional amount of refrigerant by pipe length (A)	kg
Corrective amount of refrigerant by system HP (B)	kg
Additional amount of refrigerant	kg