Emerson DE User Manual

Restricted airflow through the condenser coil will reduce the operating efficiency of the unit and can 

result in high compressor head pressure and loss of cooling.
Clean the condenser coil of all debris that will inhibit air flow. This can be done with compressed air 

or commercial coil cleaner. Check for bent or damaged coil fins and repair as necessary. In winter, do 

not permit snow to accumulate around the sides or underneath the condenser.
Check all refrigerant lines and capillaries for vibration isolation. Support as necessary. Visually 

inspect all refrigerant lines for signs of oil leaks.

The system refrigerant level must be periodically checked. This is easily done by the following proce-

dure:
1. Adjust temperature setpoint in the unit so that the compressor will run continuously.
2. The refrigerant level is visible through two sight glasses on the receiver, and will vary with 

ambient temperature. 
a. 40°F (4.4°C) and lower – Midway on the bottom sight glass. 
b. 40 to 60°F (4.4 to 15.6°C) – Bottom sight glass should be clear with liquid. 
c. 60°F (15.6°C) and above – Midway on the top sight glass.

3. Return temperature setpoint to desired number.