9
SERVICE INSTRUCTIONS (Trouble Shooting Guide)
1.
High head pressure and high back pressure:
A.
Condenser coil clogged or restricted.
B.
Condenser fan motor defective.
C.
Air discharge in rear of cabinet restricted
2.
Low back pressure and low head pressure:
A.
Restriction in system.
B. Refrigerant
undercharged.
C.
Leak in system.
3.
Pressures normal – cabinet warm:
A.
Coil blocked with frost or ice (see #4).
B. Refrigerant
undercharged.
C.
Control set too warm.
4.
Coil blocked with frost or ice:
A.
Defective temperature control.
B.
Doors aren’t sealing when closed.
C.
Evaporator fan motor defective.
D. Low
voltage.
5.
Compressor starts and runs – but cycles on overload:
A. Low
voltage.
B.
Overload protector defective.
C.
High head pressure (see#1).
6.
Compressor will not start – hums, but cycles on overload:
A. Low
voltage.
B. Relay
defective.
C. Overload
defective.
D.
High head pressure (see #1).
