Daikin DBC Series Installation Instructions Manual page 14

Air Conditioning Start-Up Procedure and
Checklist
Begin with power turned off at all disconnects.
1. Turn thermostat system switch to "Cool," and fan
switch to "Auto" and turn temperature setting as high
as it will go.
2. Inspect all registers and set them to the normal open
position.
3. Turn on the electrical supply at the disconnect.
4. Turn the fan switch to the "ON" position. The blower
should operate after a 7 second delay.
5. Turn the fan switch to "Auto" position. The blower
should stop after a 60 second delay.
6. Slowly lower the cooling temperature until first stage
COOL (LOW COOL) starts. The blower, both fans,
and first stage compressor should now be operating.
Allow the unit to run 10 minutes, make sure cool air is
being supplied by the unit.
7. Lower the cooling temperature further until second
stage COOL (HIGH COOL) starts. The blower, both
fans, and both compressors should now be operating.
Allow the unit to run 10 minutes, make sure cool air is
being supplied by the unit.
8. Turn the temperature setting to the highest position,
stopping the unit. The indoor blower will continue to
run for 60 seconds.
9. Turn the thermostat system switch to "OFF" and
disconnect all power when servicing the unit.
HIGH VOLTAGE!
Disconnect all power before
servicing or installing this unit.
Multiple power sources may be
present. Failure to do so may cause
property damage, personal injury or
death.
Heat Pump Start-Up Procedure
1. Check the cooling mode for the heat pump in the
same manner as above. The reversing valve is
energized when the thermostat is placed in the
cooling position. A clicking sound should be noticeable
from the reversing valve. By lowering the temperature
setting to call for cooling, the contractor is energized.
The compressor, blower and fan should then be
running. After the cooling mode is checked out, turn
the thermostat system switch to "OFF".
2. Turn the thermostat system switch to "HEAT" and fan
switch to "AUTO".
3. Slowly raise the heating temperature setting. When
the heating first stage makes contact, stop raising
the temperature setting. The compressor, blower and
fan should now be running with the reversing valve in
the de-energized (heating) position. After giving the
unit time to settle out, make sure the unit is supplying
WARNING
heated air.
4. If the outdoor ambient is above 80°F, the unit may
trip on its high pressure cut out when on heating. The
compressor should stop. The heating cycle must be
thoroughly checked, so postpone the test to another
day when conditions are more suitable but-DO NOT
FAIL TO TEST.
If the outdoor ambient is low and the unit operates
properly on the heating cycle, you may check the
pressure cutout operation by blocking off the indoor
return air until the unit trips.
5. If unit operates properly in the heating cycle, raise
the temperature setting until the heating second stage
makes contact. Supplemental resistance heat, if
installed should now come on. Make sure it operates
properly.
NOTE: If outdoor thermostats are installed the
outdoor ambient must be below the set point of
these thermostats for the heaters to operate. It may
be necessary to jumper these thermostats to check
heater operation if outdoor ambient is mild.
6. For thermostats with emergency heat switch, return
to step 11. The emergency heat switch is located
at the bottom of the thermostat. Move the switch to
emergency heat. The heat pump will stop, the blower
will continue to run, all heaters will come on and the
thermostat emergency heat light will come on.
7. If checking the unit in the wintertime, when the
outdoor coil is cold enough to actuate the defrost
control, observe at least one defrost cycle to make
sure the unit defrosts completely.
Refrigeration Sequence Check
With the disconnect switch open, remove the field
connected thermostat wire from terminal R on TB1
terminal block. Place a jumper across terminals R and
G, and across R and Y on TB1 terminal block. Close the
disconnect switch. The following operational sequence
should be observed:
1. Current through primary winding of transformer
TRANS1 energizes the 24-volt control circuit.
2. To simulate a mechanical call for cooling from the wall
thermostat, place a jumper across terminals R and Y1
of terminal block TB1.
3. UNIT WITH ECONOMIZER OPTION: The
compressor circuit is interlocked through terminals
3 and 4 of the economizer module. If the outdoor air
enthalpy (temperature and humidity) is not suitable
for cooling, the economizer terminals will be closed
permitting compressor to be energized.
4. The belt drive blower contractor closes its contacts
L1, L2 and L3 to T1, T2 and T3 to provide power to
the supply fan motor.
5. Check supply fan rotation. If the supply fan is rotating
in the wrong direction, disconnect and lock off Single
Point Power Block. Do not attempt to change load
side wiring. Internal wiring is set at the factory to
assure that the supply fan and compressors all rotate
in the proper direction. Verification of correct supply
fan rotation at initial startup will also indicate correct
compressor rotation. Reconnect power and check for
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