13
R
e
v
is
ió
n
: 0
5
R
e
f.:
M
A
N
U
_
V
B
Z
1
6
/0
2
/2
0
1
7
PROBLEM
POSSIBLE SOLUTION
Compressors start, but starting
remains in circuit.
1.- Low voltage.
2.- Unit wired incorrectly.
3.- Starting capacitor seal.
4.- Running capacitor defective.
5.- Starting relay defective.
6.- High head pressure.
7.- Bearings of pistons tight-low oil charge.
Compressor starts and runs,
but cycles on overload
1.- Low voltage.
2.- Running capacitor defective.
3.- Overload protector defective.
4.- High head pressure.
5.- Fan motor, pump, etc… , wire to wrong of overload protector.
Compressor tries to start when
thermostat closes but cuts out
on overload, start after several
attempts.
1.- Low voltage.
2.- Start capacitor defective.
3.- Overload protector defective.
4.- High head pressure.
5.- Fan motor, pump, etc… , wire to wrong of overload protector.
Compressor
starts
but
immediately
cuts
out
on
overload
1.- Starting relay contacts points welded together.
2.- Starting capacitor defective.
3.- Compressor short cycles.
Starting relay burns out.
1.- Low voltage.
2.- High voltage.
3.- Compressors short cycles.
4.- Incorrect running capacitor.
5.- Incorrect relay.
Running capacitors burn out.
1.- Line voltage too high.
Head pressure to low
1.- Insufficient refrigerant charge.
2.- Leak in the system.
3.- Cold location.
Head pressure to high
1.- Unit overcharged.
2.- Air or other non-condensable gases in system.
3.- Clogged condenser (air-cooled)
4.- Defective condenser fan motor.
5.- Unit location too hot.
6.- Restriction in expansion valve, strainer or drier.
7.- Discharge valve partially closed.
8.- Restriction in discharge line.
