Page 110 – Bulletin 100-50-9.1
12. DEFROST CONFIGURATION
The Set-up menu ensures that the minimum required 
for safe and effective execution of case defrost is entered. 
Additional features and modification of the Defrost Cycle 
(See Defrost) is performed using the Defrost Menu. There 
are two sections for configuring defrost: Operation and 
Schedule. The Operation section is used to adjust key 
parameters that affect functionality such as type of defrost, 
defrost grouping and valve positions during defrost. The 
Schedule section simply defines when defrost occurs.
12.1  DEFROST OPERATION
1.  From the default display, press the  button. e 
display will show   .
2.  Use the ▲▼ buttons to enter the administrator 
password and press SET.
3.  e display will show ; press SET.
4.  Press the ▲ button to scroll to the def(defrost 
conguration menu); press SET.
5.  Using the table below, scroll to the required parameter, 
then press SET to change.
TABLE 15  DEFROST CONFIGURATION MENU ITEMS
Display Meaning Description Selections Hide Condition
def
Defrost type Type of defrost for case/line-up
Electric  
e 
Hot gas  g 
Off time  
d
Defrost termination  
temperature set point
Temperature at which active defrost mechanism  
(heater, hot gas) deactivates
4 - 75 °F
de
Defrost termination fail-safe time Maximum elapsed time before active defrost mechanism deactivates
11-2  minutes
dd
Defrost coil drain time
Time period between deactivation of defrost mechanism and re-
initiating refrigeration
 -6  minutes
(2)
de
Min defrost time Minimum time for a defrost
1-2 minutes
fd
Fan delay temperature Temperature at which evaporator fans energize after defrost
-32 -32
(2)
de
Fan delay time Maximum elapsed time before fans resume operation
 -6 minutes
(2)
d
Liquid line solenoid defrost 
operation
Liquid line solenoid energized/de-energized during defrost
o 
e
(3)
d
Defrost pump down time
Time period after refrigerant flow has ceased prior to  
activating the defrost mechanism
 -3  
seconds
d
Defrost synchronization group Selects defrost group within line-up this case is a member of
1 -8
(4)
h
Use internal defrost schedule
Selects internal defrost schedule to used when no BAS detected on 
network
o 
e
dfd
Defrosts per day Number of defrosts per day
 -12
df
Daily start time Starts time of first defrost
 - 2359
f
Fans on during defrost Selects evaporator fan action during defrost
 
ff
(2)
d
Defrost termination sensor Selects defrost termination temperature sensor
Defrost  termination 
def 
Discharge air 
d
Time terminated 
e
(5)
def
Defrost active relay  
contract
Defrost relay energized/de-energized during active defrost. See 
active defrost.
Normally open 
oo 
Normally closed 
o
(2)
d
EEPR percent open during hot 
gas drain
% EEPR is open during drain time to allow for equalization of 
evaporator pressure to suction
 - 1%
(1)
du
Defrost current Expected defrost current 1.5 to 50 Amps
TABLE 16  HIDE CONDITIONS FOR DEFROST  
CONFIGURATION MENU ITEMS
Number Hide Condition
1 Defrost type is air or electric
2 Defrost type is air
3 Defrost type is hot gas
4 Case type is self-contained
The set-up is simplified by presenting the user with only 
the parameter selections required based on previous 
parameter value selections. Parameters that can be hidden 
in the table above are shaded                  and assigned a 
number in parenthesis. The explanations  correspond to 
those numbers.