7
START UP & ADJUSTMENTS
Pre-Start Check List
√ Verify the unit is level and has sufficient clearances for
unobstructed airflow.
√ Verify the outdoor coil and top of the unit are free from
obstructions and debris, and all equipment access/
control panels are in place.
√ Verify that the line voltage power leads are securely
connected and the unit is properly grounded.
√ Verify that the low voltage wires are securely connected
to the correct leads on the low voltage terminal strip.
√ Verify that the power supply branch circuit overcurrent
protectionissizedproperly.
√ Verify that the thermostat is wired correctly.
Start-Up Procedures
WARNING:
This unit is equipped with a crankcase heater.
Allow 24 hours prior to continuing the start up
procedures to allow for heating of the refrigerant
compressor crankcase. Failure to comply may
result in damage and could cause premature
failure of the system. This warning should be
followed at initial start up and any time the power
has been removed for 12 hours or longer.
Air Circulation - Indoor Blower
1. Set the thermostat system mode on OFF and the fan
mode to ON.
2. Verify the blower runs continuously. Check the air delivery
at the supply registers and adjust register openings for
balanced air distribution. If insufficient air is detected,
examine ductwork for leaks or obstructions.
3. Set the thermostat fan mode to AUTO and verify the
blower stops running.
NOTE: On 3 phase air handler models only - If blower
is spinning opposite of arrow direction, shut off the main
power to the unit and switch any two field wires at the
disconnect. DO NOT alter unit wiring.
Short Cycle Protection
1. Set the thermostat system mode to COOL. Observe the
temperature setting of the thermostat and gradually raise
theset-pointtemperatureuntiltheunitde-energizes.
2. Immediately lower the set point temperature of the
thermostat to its original setting and verify that the
indoorblowerisenergizedandoutdoorunitremains
de-energized.
3. After approximately 5 minutes, verify the outdoor unit
energizesandthetemperatureofthedischargeairis
cooler than the room temperature.
System Cooling
1. Set the thermostat’s system mode to COOL and the
fan mode to AUTO. Gradually lower the thermostat
temperature setpoint below room temperature and
verifytheoutdoorunitandindoorblowerenergize.
2. Verify blower wheel is spinning in direction indicated by
arrow. Feel the air being circulated by the indoor blower
and verify that it is cooler than ambient temperature.
Listen for any unusual noises. If unusual sounds occur,
determine the source of the noise and correct as
necessary.
3. Verify HI and LO refrigerant pressures.
NOTE: If refrigerant pressures are abnormal and the
compressor is rotating backwards, shut off main power to
the unit and switch any two field wires at the disconnect.
DO NOT alter unit wiring.
4. Allow the system to operate for several minutes and then
set the temperature selector above room temperature.
Verify the fan and compressor cycle off with the
thermostat. NOTE: The blower should also stop unless
fan switch is set to the ON position.
System Heating
1. Set the thermostat's system mode to HEAT and the
temperature mode to below room temperature.
2. Verify the outdoor unit and indoor fan stop running. After
5 minutes, increase the temperature on the thermostat
to it's maximum setting.
3. Verifytheoutdoorunitandindoorblowerenergize.Feel
the air being circulated by the indoor blower and verify
that it is warmer than ambient temperature. Listen for
any unusual noises. If unusual sounds occur, determine
the source of the noise and correct as necessary.
Defrost Cycle Timer
The defrost cycle timer controls the time interval of the hot
gas defrost after the defrost sensor closes. It is located in
the lower left corner of the defrost control board on the of
the control panel. Three interval settings are available: 30,
60, and 90 minutes. Time setting selection is dependent
on the climate where the unit is being installed.
• Example 1: Dryclimateof SouthernArizona - A 90
minute setting is recommended.
• Example2:MoistclimateofSeattle,Washington-A
30 minute setting is recommended.
To set the cycle timer, place the timing pin on the defrost
control board to the desired time interval post.
NOTE: All units are shipped from the factory with the
default time setting of 30 minutes. Longer settings are
recommended for drier climate areas and shorter time
intervals are recommended for moist climate areas.
Maximum heating performance can be acheived by setting
the time to 90 minutes.