Sinclair SCV-1400EB, Service Manual

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Electronic expansion valve
EXV-B
● ●
Step from 0 to 480. Controlled according to discharge
temperature superheat.
Electronic expansion valve
EXV-C
● ●
Enhanced vapor injection EXV, Step from 0 to 480.
Controlled according to temperature difference
between economizer plate heat exchanger inlet and
outlet.
Four-way valve
ST1
● ●
Closed
Solenoid valve (defrost)
SV5
● ●
Closed
Solenoid valve (by pass)
SV6
● ●
Closed
Solenoid valve (injection)
SV8A/B
● ●
Open
Water side heat exchanger
heater
-
● ●
According to water side heat exchanger anti-freezing
temperature
Water flow switch
Water-SW
● ●
After water pump (field supplied) is turned on for
2min, if water flow switch is open, water pump stops
and water flow error code appears. The compressor
can be started after the water flow is normal.
Water flow switch heater
-
● ●
Controlled according to ambient temperature, water
inlet temperature and water outlet temperature
Crank case heater
CCH
● ●
Controlled according to ambient temperature and
discharge temperature
For SCV-1800EB:
Component Wiring diagram label
180kW
Control functions and states
Inverter compressor
BP1/2 ●
Controlled according to load requirement from hydronic system.
DC fan motor FAN ●
Controlled according to outdoor heat exchanger pipe temperature.
Electronic expansion valve EXV
●
Position (steps) from 0 (fully closed) to 480 (fully open), controlled
according to outdoor ambient temperature, discharge
temperature, suction superheat, compressor speed and refrigerant
system pressure.
Four-way valve ST1
●
Off
5.3 Compressor Output Control
The compressor rotation speed is controlled according to the load requirement. Before compressor startup, the outdoor unit
determines the compressor target speed according to outdoor ambient temperature, discharge temperature and then runs the
appropriate compressor startup program. Once the startup program is complete, the compressor runs at the target rotation
speed.
The compressor speed is controlled according to two parts in normal operation:
In cooling mode: In a single system, the compressor speed is controlled according to the water outlet temperature and water
outlet setting temperature. In a combination system, the compressor of master unit is controlled according total water outlet
temperature and water outlet setting temperature, the compressor of the slave unit is controlled according to water inlet and
water outlet temperature. Both in a single system and combination system, the compressor speed is limited by the inverter
module temperature (calculated value), ambient temperature, discharge temperature, discharge pressure and air side heat
exchanger refrigerant total outlet temperature.