Cooling/Heating Start Up; Economizer/Oa Damper Start-Up; Fixed Speed Compressor Startup - Daikin Rebel Applied DPSA Installation And Start-Up Manual

Cooling/Heating Start up

Supply Fan Start-up
1. Verify all duct and unit mounted isolation dampers are
open.
2. Place the unit into Fan Only through the keypad menu.
Main Menu\Quick Menu\Ctrl Mode= FanOnly
a. The fan will activate.
b. Check the manual motor protectors or that the
circuit breakers have not tripped.
c. Check the phase monitor.
3. Verify the DHL safety, if included, is opening at a
pressure compatible with duct working pressure limits.
NOTE: Supply and return or exhaust fans should be adjusted
for proper airflow during air balancing.
See "Air Balancing" on page 46

Economizer/OA Damper Start-up

1. Check whether the outdoor air is suitable for free
cooling by displaying the keypad menu
ViewStatus\Economizer\FreeClgStatus=Avai
verify that the enthalpy changeover control is working
properly. You may want to take temperature and humidity
measurements.
2. At the keypad, set the cooling setpoint low enough so
that the controller will call for cooling. Adjust the value
Commission Unit\CoolingSet-Up\Occ Clg Spt
in
the temperature shown as Control Temp in the same
menu. In addition, on DAC units, adjust the value in
Commission Unit\CoolingSet-Up\DAT Clg Spt
temperature shown in Disch Air in the same menu.
3. Place the unit into cooling mode through the keypad
Quick Menu\Ctrl Mode = Cool Only
menu
4. Observe the outdoor air dampers:
a. If the outdoor enthalpy is low, the control algorithm
should start to modulate the dampers open to
maintain the discharge air setpoint.
b. If the outdoor enthalpy is high, the dampers should
maintain their minimum position. Look at menu
ViewStatus\Economizer\Min OA Pos
entry to another value. Verify that the dampers
move to the new minimum position setpoint.
5. If the unit is equipped with comparative enthalpy
sensors, no adjustment is necessary. MicroTech 4
compares the energy required to cool and dehumidify the
outside air vs the return air and decides which is less.
NOTE: It may not be possible to check the economizer
operation in both low and high enthalpy states on the
same day. If this is the case, repeat this procedure on
another day when the opposite outdoor air enthalpy
conditions exist.
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Fixed Speed Compressor Startup

Low ambient temperature can cause compressor damage. Do not attempt
to start up and check the refrigeration system when the outdoor air
temperature is below 50°F unless the unit is specially equipped for low
ambient operation.
Venting refrigerant to atmosphere is not allowed per federal and state laws
and local regulations and codes.
Make certain the supply and return fans are operational and
prepare for compressor operation.
If the unit contains optional compressor isolation valves, Verify
that valves are open. These are ball valves that can be opened
with a quarter turn.
Verify that the unit has not lost its refrigerant charge. Check the
compressor oil level before startup. The oil level should be at
or slightly above the center of the sight glass.
Verify that the crankcase heaters are energized. These should
operate for at least 24 hours before starting the compressors.
Main Menu\
Unavaill
or Verify that the condenser fan blades are positioned properly
and that the screws are tight
be correctly positioned within its orifice for proper airflow
across the condenser coils.
Figure 49: Condenser Fan Blade Positioning
below
below the
.
. Change this
43
CAUTION
NOTICE
(Figure 46). The fan blade must
1.25"
IM 1287 • REBEL APPLIED ROOFTOP
Unit Operation