www.DaikinApplied.com 77 IM 1287-6 • REBEL APPLIED ROOFTOP
Servicing High Voltage Control Panel
Components
DANGER
LOCKOUT/TAGOUT all power sources prior to servicing the unit. Hazardous
voltage may cause serious injury, death, and property damage. Disconnect
electric power before servicing equipment. More than one disconnect may
be required to de-energize the unit.
Disconnect all electric power to the unit when servicing control
panel components. Unless power is disconnected to the unit,
the components remain energized. Always inspect units for
multiple disconnects to ensure all power is removed from the
control panel and its components before servicing.
Before Start-up
1. Verify that the unit is completely and properly installed
with ductwork connected.
2. Verify that all construction debris is removed, and that
the lters are clean.
3. Verify that all electrical work is complete and properly
terminated.
4. Verify that all electrical connections in the unit control
panel and compressor terminal box are tight, and that the
proper voltage is connected.
5. Verify all nameplate electrical data is compatible with the
power supply.
6. Verify the phase voltage imbalance is no greater than
+/- 4%.
7. Manually rotate all fans and verify that they rotate freely.
8. Verify all fasteners on the fan assemblies are still tight.
9. Verify that the evaporator condensate drain trap is
installed and that the drain pan is level.
10. If unit is curb mounted, verify that the curb is properly
ashed to prevent water leakage.
11. Before attempting to operate the unit, review the control
layout description to become familiar with the control
locations.
12. Review the equipment and service literature, the
sequences of operation, and the wiring diagrams to
become familiar with the functions and purposes of the
controls and devices.
13. Verify that the crankcase heaters are operating. These
should operate for at least 24 hours before starting the
compressors.
14. Determine which optional controls are included with the
unit.
NOTE: If desired, you can signicantly reduce all MicroTech
internal control timers by the changing the entry
under keypad menu Main Menu\Commission Unit\
Timer Settings\Startup,Recirculate = (from 180s to
60s min where 60s is the number of seconds you
want the unit to operate with fast timers).
Initial Manual Mode Start-Up
Initial Start-up should be performed in manual control mode
before proceeding to the cooling/heating start up.
Power Up
1. Close the unit disconnect switch. With the control system
switch in the OFF position, power should be available
only to the control circuit transformer (T1) and the
compressor crankcase heaters.
2. Turn the Switch to ON. Power should now be supplied to
the control panel, and the LEDs on MCB1 should follow
the normal start-up sequence.
Supply Fan Start-up
1. Verify all duct and unit mounted isolation dampers are
open.
2. Place the unit into Manual Control Mode through the
keypad menu Main Menu\Manual Control\Manual Ctrl =
Manual
3. Activate the Fan through the keypad menu Main Menu\
Manual Control\Supply Fan = On; Set SAF Cap Cmd =
40%
a. Check Fan rotation for proper rotational direction
4. Speed the fan Up through the keypad menu Main Menu\
Manual Control\SAF Cap Cmd = 100%
a. Check the manual motor protectors or that the
circuit breakers have not tripped.
b. Check the phase monitor.
5. 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 airow during air balancing.
See “Air Balancing” on page 81
To Next Page
Loading...
