Sanyo CHDXR07263, CHDXR09663 Operation of Solenoid Valves, Refrigerant Control Valve RCV

6. Operation of Solenoid Valves

W-2WAY ECO-i SYSTEM Control Functions

6-1. Refrigerant Control Valve [RCV]

The main purpose of this valve is to detect the flow of refrigerant (refrigerant volume) on the indoor-unit side when the outdoor unit heat exchanger is functioning as a condenser. When the valve determines that there are signs of a low refrigerant level, refrigerant is supplied from the receiver tank to the system.

(1)The OFF conditions take priority over the ON conditions for this valve.

(2)This valve is OFF when the outdoor unit is stopped.

(3) This valve is ON when special control is in progress. Hp 1

(4) Control during normal operation

(A) Cooling operation

This valve turns ON when symptoms of insufficient refrigerant gas occur at an indoor unit.

This valve turns ON when the outdoor air temperature is 59°F or below. (Under these conditions the high pressure is low and refrigerant flow becomes poor.)

This valve turns OFF when symptoms of refrigerant overcharge are detected at the outdoor unit.

(B) Mixed cooling/heating operation

The RCV turns ON at stopped outdoor units when the heat exchanger at anoth- er outdoor unit is functioning as a condenser.

6-2. Refrigerant Balance Valve [RBV] – Gas Purge Valve

The main purpose of this valve is to detect the flow of refrigerant (refrigerant volume) on the indoor-unit side when the outdoor unit heat exchanger is functioning as an evaporator. When the valve determines that there are signs of excess refrigerant, refrigerant is recovered at the receiver tank.

This valve is ON during heating operation and when the outdoor unit heat exchanger is functioning as an evapora- tor during mixed heating/cooling operation. It also turns ON in order to recover refrigerant at the outdoor unit after heating operation is stopped.

* This valve is never turned ON at the same time with the RCV.

(1)The OFF conditions take priority over the ON conditions for this valve.

(2)This valve turns ON for 30 – 50 seconds after the outdoor unit stops, and then turns OFF.

(3)This valve turns ON once after the outdoor unit starts.

(A) Heating operation Lp

This valve is ON during heating operation and when it turns ON for the purpose of recovering refrigerant in the outdoor unit at the end of the heating operation. After the valve turns from ON to OFF, it will not turn ON again for 15 minutes.

This valve turns ON when poor refrigerant flow at an indoor unit is detected, and when symptoms of overcharge are detected, if the heat exchanger at the outdoor unit is functioning as an evaporator.

(4)This valve turns OFF when an abnormal drop in discharge gas temperature is detected.

(5)This valve turns OFF when a drop in the detected receiver tank temperature contin-

ues for a set length of time, and when liquid back-flow is judged to be occurring.

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