CSR-20 & CSR-40, September 1999
µ
P-D Controller
Initiating a Manual Defrost
4-19
Initiating a Manual Defrost
With the unit On/Off switch ON:
1.
Press the DEFROST key. The display flashes “ENTER
DFRST”.
2.
Press the ENTER key.
• If the unit operating conditions allow a manual defrost
(e.g. evaporator coil temperature is less than 10 C [50
F]), the display briefly shows “LOAD DFRST”. The
unit enters defrost as the Defrost LED turn ON. The
defrost cycle automatically terminates.
NOTE: If the ENTER key is not pressed within
10 seconds, the controller will default (return) to
the Standard Display.
• If unit operating conditions do NOT allow defrost, the
display shows “DFRST INVAL” for 3 seconds.
3.
The controller then returns to the Standard Display.
IN RANGE
DEFROST SUPPLY RETURN PWRLMT ALARM
HEAT
NULL
MOD
COOL
SETPOINT
TEMPERATURE
DATA
DATA
IN RANGE
DEFROST SUPPLY RETURN PWRLMT ALARM
HEAT
NULL
MOD
COOL
SETPOINT
TEMPERATURE
DATA
DATA
IN RANGE
DEFROST SUPPLY RETURN PWRLMT ALARM
HEAT
NULL
MOD
COOL
SETPOINT
TEMPERATURE
DATA
DATA
Initiating a Full Pretrip
To perform a Full Pretrip test, turn the unit On/Off switch ON:
NOTE: The controller will not perform an auto-
matic pretrip test until all alarms have been cor-
rected and cleared.
1.
Press the PRETRIP key. The display flashes “ENTER
PTRIP”.
2.
Press the ENTER key. The display briefly shows “LOAD
PTRIP”. The controller then conducts a Full Pretrip Test.
3. When the Pretrip test is complete, the display returns to
the Standard Display (e.g. setpoint and controlling sensor
temperatures). The unit returns to normal operation.
IN RANGE
DEFROST SUPPLY RETURN PWRLMT ALARM
HEAT
NULL
MOD
COOL
SETPOINT
TEMPERATURE
DATA
DATA
IN RANGE
DEFROST SUPPLY RETURN PWRLMT ALARM
HEAT
NULL
MOD
COOL
SETPOINT
TEMPERATURE
DATA
DATA
P
