V6 VRF 50Hz
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4.3 Startup Control for Heating Operation
Table 3-4.2: Component control during startup in heating mode
Control functions and states
Controlled according to load requirement,
operating frequency increased by 1 step / sec
Open once the four-way valve has opened,
controlled according to outdoor ambient
temperature and load requirement
Electronic expansion valve
A
Position (steps) from 0 (fully closed) to 480 (fully
open), controlled according to discharge superheat
Electronic expansion valve B
Electronic expansion valve C
Position (steps) from 0 (fully closed) to 480 (fully
open), controlled according to temperature
different between plate heat exchanger inlet and
outlet
Solenoid valve (oil balance)
Closed for 200 secs, open for 600 secs, then closed
Solenoid valve (fast
defrosting (in heating) and
unloading (in cooling))
Open for 4 mins, then closed
Solenoid valve (EXV bypass)
Solenoid valve (indoor units
bypass)
Controlled according to load requirement
Solenoid valve (inverter
compressor A vapor
injection)
Controlled according to inverter compressor A
Solenoid valve (inverter
compressor B vapor
injection)
Controlled according to inverter compressor B
Solenoid valve (inverter
compressor B pressure
balance)
Open before compressor B startup