Figure 14: Pump-Down Functionality With Temperature Sensor - Emerson Copeland EazyCool ZXME020E Application Manuallines

The functionality of parameter G11 protects the cooled goods in case of component damage, eg, the
liquid line solenoid is mechanically blocked and not able to stop refrigerant mass flow. In that case
the compressor cut-out pressure will not be reached and the compressor will continue to run. The
only limitation to stop the compressor is the maximum pump-down time. G11 should be adjusted in
a way that, at all operating conditions, it allows pump-down to compressor cut-out value C02 plus a
defined safety time, eg, 2 minutes.
2.14.4 Internal pump-down with temperature sensor (case temperature)
It is also possible to carry out pump-down functionality in case a temperature sensor is used for
temperature control (not part of the standard delivery). Parameters G56 and S07 have to be set up
as described in Chapter 2.14.3 "Pump-down with room thermostat".

Figure 14: Pump-down functionality with temperature sensor

The control of a cold room or cooling cabinet can be realized with a temperature sensor (change
parameter G01 according to the probe location). Parameter A19 must be set up as thermostat
temperature. The temperature setpoint is defined by parameter G02. Adjust the temperature range
by means of positive differential value G03.
If the temperature increases and reaches setpoint plus differential, the liquid line solenoid output
relay will energize the coil to open the valve. The compressor will be controlled by suction pressure.
The temperature value is to be set between two parameters (G04 and G05).
In case of fault in the thermostat probe the opening and the closing of the solenoid valve relay are
timed through limp along parameters (G06 and G07).
Parameter Factory settings
A19 0 = Not used = nu
C01
4 bar rel
C02 2 bar rel
C05 1 = Suction pressure probe = SuP
G01 0 = Not used = nu
G02 +2°C
G03 +1°C
G04 -10°C
G05
+15°C
G06 2 minutes
G07 1 minute
G11
3 minutes
G56 0 = Not used = nu
S07 0 = Not used = nu
Table 24: Internal pump-down with temperature sensor
C6.1.6/0117-1017/E
Pump-down settings / Comments
2 = Thermostat temperature = tnt
Cut-in value for pump-down
Cut-out value for pump-down, eg, 0.2 bar rel
2 = Case temperature probe = CSt
4 = Thermostat temperature = tnt
Setpoint for temperature, eg, +2°C for meat
Positive differential defines upper cut-out
value
Lower setpoint limit
Upper setpoint limit
On time in case of probe failure
Off time in case of probe failure
Maximum pump-down time
1 = Yes
7 = Liquid line solenoid = LLS
25