Sanyo CHDXR09663, CHDX09663, CHDX07263, CHDXR07263* service manual Protection control

3. Compressor Control

W-2WAY ECO-i SYSTEM Control Functions

3-6-2. Condensation Temperature (Tc) Control:

Control of Indoor Units Operating either in Cooling Mode or Heating Mode

PX=125.6°F		Thermostat OFF	Area D
	PX –0.1
		Horsepower decrease	Area C
118.5
118.4		Horsepower increase
			Area B
116.6		prohibited
116.4
		Horsepower increase	Area AB
113.0		permitted
112.8		Horsepower increase	Area A
		permitted

*Depending on the maximum requirement level of the indoor unit, the judgment temperatures for each area may vary as shown in the figure (example).

118.4

116.6

		109.4
100.4		107.6
98.6
0	15		30

Maximum requirement level [L]

1

(1)For indoor units which are operating in Heating mode, if one unit is selected for a test run, the air intake tem- perature difference is ignored, however Tc control is performed according to the figure above in order to pre- vent excessive load. (This is used for test run checks, etc.)

(2)Even within the same area, the compressor capacity varies depending on the refrigerant temperature.

(3)Temperature PX is the coefficient value used to correct for any deviation with the high pressure or condensa- tion temperature. It may vary. (At the time of shipment it is 127°F.)

(4)If the condensation temperature (Tc) enters area D and the thermostat turns OFF, the next time the compressor starts it may restart from a lower capacity.

3-6-3. Protection control

Protection control consists of 2 types of protection: discharge temperature protection and current protection. The limit values from this protection control are incorporated into the output compressor capacity increase/decrease values that were calculated from control based on the temperature at the indoor unit heat exchanger coil (roadmap control).

*In some cases, the control shown below may stop the compressor, issue a warning, or reduce the compressor capacity.

(1)Discharge Temperature Protection

During operation when only a single outdoor unit is installed, the air discharge temperature level is determined (the highest value is used), and the compressor capacity is limited, by using the air discharge temperature of the operating compressor (as shown in the tables below).

Air discharge temperature level: Highest level among the air discharge temperature levels of all compressors

Air discharge temp. level	Discharge temp. °F	Horsepower limit
5	221	Decrease by 2 horsepower
4	219	Decrease by 1 horsepower
3	217	Decrease by 0.5 horsepower
2	212 ~ Less than 217	Prohibit horsepower increase
1	208 ~ Less than 212	Permit horsepower increase (slowly)
0	Less than 208	No control

The values shown in the table above are reduced to the values calculated by roadmap control.

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