Uline H-8771 Manual Del Usuario página 6

OPERATING ISSUE
Unit displays AL and
audio alarm is sounding
during start up or while
operating.
System is on and
display is showing ON
but unit is not supplying
conditioned air.
Power is supplied but
control is blank.
System trips breaker on
startup.
Display shows 32 and
unit will not turn on
cooling.
Chatter or hum is heard
from the control box
while the system is
operating.
Supply air flow is limited,
and/or water is dripping
from the front of the
system.
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TROUBLESHOOTING CONTINUED
CAUSES
Microprocessor board has detected
high pressure. The high pressure
switch is tripped.
System is in timeout (F or C is
flashing), control is set above room
temperature or control is adjusted
out of operating parameters or not
in the correct operational mode.
Low voltage circuit is not engaged.
Incoming power is incorrect, breaker
is undersized or faulty, and/or power
cable is too long and/or undersized.
No connection of temperature
sensor to Microprocessor.
Temperature Sensor malfunction.
Incoming source power is poor or
low voltage component is faulty.
Supply or return air is blocked or
restricted, and/or the evaporator coil
is freezing.
RECOMMENDATIONS
High pressure is normally caused by
reduced condenser air flow.
Check for restriction in ducting.
Check for condenser air system
ventilation.
Check condenser motors and/or blowers
for proper operation.
High pressure is a manual reset type.
To reset, press the button labeled HP
reset located in the condenser make-up
air inlet on the back of A/C unit (it will
click when resetting).
Wait two minutes, and recheck display.
Check source power breaker and verify
incoming power to connector. Call Uline
Customer Service at 1-800-295-5510 for
assistance.
Verify the circuit and power cable is
within the system's specifications, consult
with a licensed electrician or call Uline
Customer Service at 1-800-295-5510
for assistance.
Call Uline Customer Service at
1-800-295-5510 for assistance.
Check for proper incoming voltage;
remove excess or undersized power
cable. Call Uline Customer Service at
1-800-295-5510 for assistance.
Verify that supply and return air are not
blocked and duct work is installed to
specification, remove or add duct as
needed, check air filter for blockage.
0920 IH-8771