Toshiba RAV-SM2804AT7ZG, RAV-SM2804AT8ZG-E 12. SV2 valve control, Oil recovery control

12.SV2 valve control

The conditions for opening and closing the SV2 valve are shown in the table below.

			SV2 Valve “Open” Conditions	SV2 Valve “Close” Conditions
		(1)	When operation stopped after operating	When operation started after operating or when 30 minutes
Non-operation
		(2)	When power placed “ON”	elapsed after opening SV2 under conditions (1) (2)
During Cooling		(3)	When 30 second elapses after first startup	When 8 minutes elapsed after starting operation.
			operation when power ON at TO ≤ 5° C
Operations
		(4)	When Ps ≤ 0.23 MPa	When Ps ≥ 0.27 MPa
During Heating		(5)	When 30 second elapses after first startup	When 8 minutes elapsed after starting operation or when
			operation when power ON at TC < 26°C	TC ≥ 26°C
Operations
		(6)	When Ps ≤ 0.14 MPa	When Ps ≥ 0.19 MPa
	During	(7)	When conditions for defrost satisfied.	When 4-way valve is OFF during defrost startup.
	Defrost			When 2 minutes elapsed after four-way valve is ON after
	Operation	(8)	When conditions for defrost satisfied.
				defrost completion

Defrost	Defrost
start condition	completion condition

Defrost operation

66rps

Compressor revolution number

36rps

4-way valve	ON
	OFF
	2 minutes
SV2	Open
	Close

13.Oil recovery control

1)This control enables periodic recovery of oil accumulating in the indoor unit or in the exchange pipe.

2)After continuous operation for 240 minutes, the lower limit for the compressor revolution number is raised for 2 minutes and oil is recovered.

	Control Conditions	Control Details
During Cooling	Continuous cooling operation for 240 minutes	Lower limit for compressor revolution number placed to 56 rps per
		2 minutes
During Heating	Continuous heating operation for 240 minutes	Lower limit for compressor revolution number placed to 70 rps per
		2 minutes

3)

	When low	The compressor rotation speed is raised to the lower limit
During startup of oil recovery control, the compressor		during control.
revolution number during operation is lower than the		Operate according to indoor commands without lowering
revolution number of the lower limit for control details.
	When high	the compressor rotation speed to the lower limit.
		(In this case, the timer counts 2 minutes.)

4)When the DOWN zone and the HOLD zone (UP prohibition) are superimposed for example during current release control or discharge temperature release control, DOWN zone and the HOLD zone have priority over oil recovery control.

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