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High Discharge Pressure Alarm
The high discharge pressure alarm will
enable if the high pressure switch opens.
This alarm will disable the compressor but
allow the supply fan to operate.
Low Suction Pressure Alarm
The low suction pressure alarm will activate
and turn the compressor off if the low suction
pressure switch is open for 10 seconds. The
alarm will deactivate if 15 minutes has
expired and the low pressure switch has
closed. If the alarm is activated again within
two hours, the unit power must be cycled off
and on.
Maintenance
See back of the manual for maintenance log.
At least once each year, a qualified service
technician must check out the unit. Supply
fans, evaporator coils and air filters must be
inspected monthly.
See Startup section for information on air
flow adjustment.
DX Cooling
Set unit controls to cooling mode of operation
with supply fans on. Check the fans for
correct operating direction, amperage and
voltage. Check compressor operation,
rotation, amperage and voltage to the unit
nameplate (check the amperage on the load
side of the compressor contactor). Check for
24V signal across the reversing valve
terminals.
Condensate Drain Pans
Drain pans will have moisture present and
require periodic cleaning to prevent
microbial growth. Cleaning of the drain pans
will also prevent any possible plugging of the
drain lines and overflow of the pan itself.
Cleaning of the drain pans and inside of the
unit must be done only by qualified
personnel.
Supply Fans
Supply Fan Lubrication
Supply fan motors are permanently
lubricated and require no oiling.
Filter Replacement
Monthly filter inspection is required to
maintain optimum unit efficiency. It is
strongly recommended that filter media be
replaced monthly.
Improper installation, adjustment,
alteration, service or maintenance can
cause property damage, personal
injury or loss of life. Installation and
service must be performed by a
qualified installer. Keep a copy of this
IOM with the unit.
Blower wheels must be inspected for
excessive dust build up periodically
and cleaned if required. Excessive
dust build up on blower wheels may
cause an unbalanced state; leading to
vibration and/or component failure.
Damages due to excessive dust build
up will not be covered under factory
warranty.
Electric shock hazard. Shut off all
electrical power to the unit to avoid
shock hazard or injury from rotating
parts.
WARNING
CAUTION
WARNING