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PG2021_SWC-V-ECM_02
2-pipe Control Logic -With 6-way modulating Valve Configuration
COOL MODE
When unit is turned on in cooling mode:
If Tr ≥ Ts + 1ºC (Modbus 300033 setting), MTV1 is turned on. AUX1 is closed. Fan is turned on at setting speed.
DA2 is turned on at 0VDC for 2 minutes, then check Ti1,
When Ti1<=8ºC, DA2 output is based on water temperature difference (Ti1/Ti2) and Modbus parameter 300027 setting
PID calculation. The output is 4~0VDC.
When 8<Ti1<=10ºC, DA2 output is based on water temperature difference (Ti1/Ti2) and Modbus parameter 300027
setting minus 1 PID calculation. The output is 4~0VDC.
When 10<Ti1<=12ºC, DA2 output is based on water temperature difference (Ti1/Ti2) and Modbus parameter 300027
setting minus 2 PID calculation. The output is 4~0VDC.
When 12<Ti1<=15ºC, DA2 output is based on water temperature difference (Ti1/Ti2) and Modbus parameter 300027
setting minus 3 PID calculation. The output is 4~0VDC.
When 15<Ti1<=28ºC (Modbus 300017 setting), DA2 output is kept at 0VDC.
When Ti1>28ºC(Modbus 300017 setting), DA2 output is 4VDC. and report pre-heat alarm.
If Tr < Ts-1ºC (Modbus 300033 setting), then cool operation is terminated and MTV1 and AUX1 are turned off. Indoor fan
runs at set speed. DA2 output is 5VDC.
When unit is turned off, MTV1 and AUX1 are off. DA2 is 5VDC. Fan is turned off delaying 30s.
LOW TEMPERATURE PROTECTION OF INDOOR COIL IN COOLING MODE
If Ti1
≦
2 ºC for 2 minutes:
MTV1 is turned OFF.
DA2 is set to 5 VDC.
Indoor fan is turned on to Medium speed if fan runs at low speed.
If Ti1
≧
5ºC for 2 minutes:
MTV1 is turned ON.
DA2 is set to original status.
Indoor fan is changed to setting speed.
FAN MODE
Indoor fan speed can be adjusted for low, medium and high. If fan speed is set auto by Modbus, fan is running at low speed.
HEAT MODE
Without Electrical Heater
（
Modbus300047=0
）
When unit is turned on in heating mode:
When Tr ≤ Ts - 1 ºC(Modbus 300033 setting) , MTV2 and AUX2 is turned on. DA2 is at 10VDC for 2 minutes, then check
Ti1:
If Ti1 < 28ºC (Modbus 300017 setting), fan is turned on at low speed. DA2 is at 10VDC.
If 28ºC<Ti1< 28
（
Modbus 3000017 setting
）
+4ºC, fan is on at original state. DA2 is at original state.
If Ti1 ≥ 28
（
Modbus 3000017 setting
）
+4ºC, fan is on at setting speed. DA2 output is based on water temperature
difference (Ti1/Ti2) and Modbus parameter 300028 setting PID calculation. The output is 6~10VDC.
If Ti1 sensor is damaged, fan runs at setting speed.
When Tr > Ts+1ºC (Modbus 300033 setting, MTV1 and AUX2 is turned off. DA3 is at 5VDC. Fan is turned on at lowest
speed.
When unit is turned off, MTV1 and AUX2 is turned off. DA2 is at 5VDC. Fan is turned off delaying 2 minutes.
With Electrical Heater as booster
（
Modbus300047=1
）
When unit is turned on in heating mode:
When Tr ≤ Ts - 1 ºC(Modbus 300033 setting) , MTV2 and AUX2 is turned on. Fan is turned on at setting speed. DA2 is at
10VDC for 2 minutes, then check Ti1:
If Ti1 < 28ºC (Modbus 300017 setting), EH is turned on. DA2 is at 10 VDC.
If 28ºC<Ti1< 28
（
Modbus 300017 setting
）
+4ºC, EH is kept at original state. DA2 is at original state.
If Ti1 ≥ 28
（
Modbus 300017 setting
）
+4ºC, EH is turned off. DA2 output is based on water temperature difference
(Ti1/Ti2) and Modbus parameter 300028 setting PID calculation. The output is 6~10 VDC.
Cooke Industries - Phone: +64 9 579 2185 Email: [email protected] Web: www.cookeindustries.co.nz
