Airwell YCV280, Installation And Maintenance Instructions Manual

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3. Outdoor control
(1) Compressor startup control
On startup, inverter compressor will keep for 3 min at 60rps, then if TdiSH is still less than 25degree,
compressor will increase frequency up to 100rps. If startup is for 15min or TdiSH is more than 25degree,
quit startup and enter normal operation. In startup operation, the limitation frequency operation will
be in priority, such as high pressure too high, discharging temp. too high, suction pressure too low,
overcurrent.
After entering normal operation, when inverter compressor frequency arrives 100rps, fixed frequency
compressor starts up, but if inverter compressor frequency is down to below 30rps, fixed frequency
compressor is OFF.
(2) Compressor operation control
It will be controlled by the target pressure.
In heating mode, the target high pressure:
When Ta>-7degree, target high pressure is 28Kg 0.8Kg;
When Ta<=-7degree, target high pressure is 24Kg 0.8Kg
In cooling mode, the target low pressure
When the running indoor capacity is over 5HP, if Ta>=21degree, target pressure Ps=8Kg (4degree)
0.5Kg; if 21degree>Ta>=15degree, target pressure Ps=7Kg(0degree) 0.5Kg.
(3) Fan motor control
a. In cooling mode
Startup procedure: When compressor starts up, outdoor motor will not run right now, when high pressure
reaches 2.1MPa, outdoor motor begins to run.
In operation, the motor will be controlled by high pressure. When high pressure reaches 2.1MPa,
outdoor motor will run at class-1 speed; if pressure is more than 2.1MPa, outdoor motor will increase
one class at interval of 60 seconds; if pressure is over 2.6MPa, outdoor motor will rise up to class-7.
If pressure is less than 1.9MPa for 60 seconds, fan motor will decrease one class. If less than 1.8MPa
for 60 seconds, fan motor will stop.
b. In heating mode
Motor control in startup procedure: Pd<set p0.3MPa.If Pd goes up, decrease outdoor motor
speed. 1 minute later, if Pd>=(set pr0.50MPa), outdoor motor stops. When defrosting is over,
after 4-way valve opens, fan motor starts up.
In operation, the motor will be controlled by low pressure. When low pressure is over 0.95MPa, fan
motor will stop; when low pressure is less than 0.75MPa, for every 60 seconds, fan speed will increase
one class; when it is less than 0.65MPa for 60 seconds, fan speed will be class-7 directly.
In defrosting, outdoor motor will stop. After the defrosting is over, 4-way vavle opens, outdoor motor
will start up at heating mode.
(4) Defrosting control
When one of the running outdoors reaches the defrosting condition, it will send defrosting signal to
the master unit. After the master unit receives defrosting signal, it will send defrosting signal to the
running outdoor. Then the slave outdoor will begin defrosting.
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