Instructions / Assembly
Page 8 of 12 507296-02Cmrcool.com
The unit will remain locked out until power to the board 
is interrupted, then re-established, or until the jumper 
is applied to the TEST pins for 0.5 seconds.
NOTE:  The  defrost  control  board  ignores  input  from  the 
low pressure switch terminals as follows:
• During the TEST mode
• During the defrost cycle
•
•
If the TEST pins are jumpered and the 5-minute delay 
is  being  bypassed,  the  LO  PS  terminal  signal  is  not 
ignored during the 90-second start-up period.
Diagnostic LEDs
Defrost Board Diagnostic LEDs
Green LED
(DS2)
Red LED
(DS1)
Condition
OFF OFF
ON
Fault & Lockout Codes
OFF
OFF ON
OFF
ON OFF
Table 3. Defrost Control (CMC1) Diagnostic LEDs
System Performance
the suction superheat value to judge performance. When 
checking  performance  of  a  unit  that  uses  an  expansion 
system performance. 
If the measured performance value varies from table value 
refrigerant to nameplate charge. It is critical that the exact 
system performance. 
components.
Model 
Suction 
Superheat +/- 3°
Liquid 
Subcooling +/- 2°
2 Ton 13
2.5 Ton
3 Ton 14
3.5 Ton 14
4 Ton
5 Ton
Table 4. Air Conditioner Unit Cooling System 
Performance Values
Model 
Suction 
Superheat +/- 3°
Liquid Subcooling 
+/- 2°
2 Ton 18
2.5 Ton
3 Ton
3.5 Ton 22
4 Ton 22
5 Ton 5
Table 5. Heat Pump Cooling System Performance 
Values
Model Liquid Subcooling +/- 2°
2 Ton
25
2.5 Ton
15
3 Ton
28
3.5 Ton
4 Ton
35
5 Ton
28
Table 6. Heat Pump Heating System Performance 
Values










