Sanyo CHDX07263, CHDXR09663, CHDX09663, CHDXR07263* Special Controls, Way Valve Adjustment Control

4. Special Controls

W-2WAY ECO-i SYSTEM Control Functions

In addition to ordinary heating and cooling operation, this system also includes the following 3 types of special con- trols for control of the system as a whole.

1.4-way Valve Adjustment Control

2.System refrigerant oil recovery control

3.Defrost control

4-1. 4-way Valve Adjustment Control

When the microcomputer is initialized immediately after power-ON, after warning output, and all outdoor units are				1
kept stopped for a preset period (standard = 60 minutes) , the 4-way Valve Adjustment Control will be performed.
This control is intended to changeover the 4-way valve of outdoor unit. When the unit has been stopped for long
period, and if refrigerant has accumulated somewhere in the tubing, recovery of the refrigerant is performed. This
control can also compensate for tubing thermal loss by radiation during heating start as well as for oil recovery.
(1) Cooling control when the outdoor unit heat exchanger is acting as a condenser
		Control time	60 seconds
		Outdoor units	All outdoor units operate at the maximum horsepower.
		Electronic Thermostat	Valves at all indoor units operate at a fixed pulse according to the indoor unit capacity.
		Expansion Valve
	Indoor
RAP valve kit		Valve kits at all indoor units operate in Cooling mode (OFF status).
			units
	Fan	Fan operates at the set fan speed or stops, depending on the indoor unit operation
			mode.

*When the above operation is finished, normal operation starts at the horsepower determined by the indoor units where thermostats are ON.

(2)Heating control when outdoor unit heat exchanger is acting as an evaporator

	Control time	Minimum 1 min - Maximum 10 min [until max (pressure sensor temp., E1) 95°F ]
	Outdoor units	All outdoor units operate at the maximum horsepower.
	Electronic Thermostat	Valves at all indoor units operate at 250 pulses as a default.
	Expansion Valve
Indoor
	RAP valve kit	Valve kits at all indoor units operate in heating mode (ON status).
units
	Fan	Fan operates at the set fan speed, stops or operates at a very low speed,
		depending on the indoor unit operation mode.

*When the above operation is finished, normal operation starts at the horsepower determined by the indoor units where thermostats are ON.

4-2. System Refrigerant Oil Recovery Control

4-2-1. System refrigerant oil recovery cycle

This control is performed using the cooling cycle during cooling operation and using the heating cycle during heat- ing operation.

4-2-2. Start of System Refrigerant Oil Recovery Control

When the oil level in an operating compressor is detected as 0 (zero), the compressor stops in 120 seconds. If this compressor repeats this operation 3 times and the oil level does not reach 2, system refrigerant oil recovery con- trol is started.

*When the compressor has stopped because the oil level is 0, a count is added to the alarm counter. The counter for this compressor is not cleared unless the oil level for that compressor reaches 2, or else alarm output occurs.

1 - 9