4.3 Startup Control for Heating Operation
Table 3-4.2: Component control during startup in heating mode
Component
Inverter compressor A
Inverter compressor B
DC fan motor A
DC fan motor B
Electronic expansion valve
A
Electronic expansion valve B
Electronic expansion valve C
Four-way valve
Solenoid valve (oil balance)
Solenoid
valve
(fast
defrosting (in heating) and
unloading (in cooling))
Solenoid valve (EXV bypass)
Solenoid valve (indoor units
bypass)
Solenoid
valve
(inverter
compressor
A
vapor
injection)
Solenoid
valve
(inverter
compressor
B
vapor
injection)
Solenoid
valve
(inverter
compressor
B
pressure
balance)
Wiring
diagram
8-12HP
14-16HP
label
COMP(A)
●
●
COMP(B)
FANA
●
●
FANB
EXVA
●
●
EXVB
●
EXVC
●
●
ST1
●
●
SV4
●
●
SV5
●
●
SV6
●
●
SV7
●
SV8A
●
●
SV8B
SV9
18-28HP
30-32HP
Controlled
●
●
operating frequency increased by 1 step / sec
●
●
Open once the four-way valve has opened,
●
●
controlled
●
●
temperature and load requirement
Position (steps) from 0 (fully closed) to 480 (fully
●
●
open), controlled according to discharge superheat
●
●
Position (steps) from 0 (fully closed) to 480 (fully
open),
●
●
different between plate heat exchanger inlet and
outlet
On
●
●
Closed for 200 secs, open for 600 secs, then closed
●
●
Open for 4 mins, then closed
●
●
Off
●
●
Controlled according to load requirement
●
Controlled according to inverter compressor A
●
●
Controlled according to inverter compressor B
●
●
Open before compressor B startup
●
●
V6 VRF 50Hz
Control functions and states
according
to
load
requirement,
according
to
outdoor
controlled according
to
ambient
temperature
37