Function General
SiUS30-1301
40
Function and Control
1. Function General
1.1
Symbol
Symbol
Electric symbol
Description or function
20S1
Y5S
Four-way valve (Main)
20S2
Y7S
Four-way valve (Sub)
DSH
—
Discharge pipe superheat
DSHi
—
Discharge pipe superheat of INV. compressor
EV
(Y1E, Y3E)
Opening of electronic expansion valve
EV1
Y1E
Electronic expansion valve for water heat exchanger
EV3
Y3E
Electronic expansion valve for subcooling heat exchanger
HTDi
—
Value of INV. compressor discharge pipe temperature (R3T) compensated with outdoor
air temperature
Pc
S1NPH
Value detected by high pressure sensor
Pe
S1NPL
Value detected by low pressure sensor
HPS
S1PH
In order to prevent the increase of high pressure when an error occurs, this switch is
activated at high pressure of 580 psi or more to stop the compressor operation.
SH
—
Evaporator outlet superheat
SHS
—
Target evaporator outlet superheat
SVG
Y4S
Solenoid valve for discharging gas from receiver
SVL
Y3S
Solenoid valve for gas charging to receiver
SVE
Y2S
Solenoid valve for oil collection from water heat exchanger
SVP
Y1S
Solenoid valve for hot gas bypass
SVSL
Y6S
Solenoid valve for non-operating unit liquid pipe closing
Tc
—
High pressure equivalent saturation temperature
TcS
—
Target temperature of Tc (condensing temperature)
Te
—
Low pressure equivalent saturation temperature
TeS
—
Target temperature of Te (Evaporating temperature)
Tfin
R1T
Radiation fin temperature
Ts
R2T
Suction pipe temperature detected by R2T (Suction pipe)
Tsh
R5T
Temperature detected by R5T-gas pipe temperature of subcooling heat exchanger gas
side (outlet temperature)
Tp
—
Calculated value of compressor port temperature
Tdi
R3T
Discharge pipe temperature detected by thermistor located the INV. compressor
discharge pipe
Tl
R6T
Liquid pipe temperature
Tg
R4T
The gas pipe temperature of water heat exchanger