Supply Fan (Blower) Section; Supply Fan (Direct-Drive) - Carrier 48JC04-06 Service And Maintenance Instructions

17 1/4"
DIVIDER
CLEANABLE
ALUMINUM
FILTER
BAROMETRIC
RELIEF
Fig. 3 — Filter Installation
To remove the filter, open the filter clips. Re-install the filter by
placing the frame in its track, then closing the filter clips.
MANUAL OUTSIDE AIR HOOD SCREEN
This inlet screen is secured by a retainer angle across the top
edge of the hood. (See Fig. 4.)
SCREWS
Fig. 4 — Screens Installed on Outdoor-Air Hood
To remove the screen, loosen the screws in the top retainer and
slip the retainer up until the filter can be removed. Re-install by
placing the frame in its track, rotating the retainer back down,
and tightening all screws.

SUPPLY FAN (BLOWER) SECTION

WARNING
ELECTRICAL SHOCK HAZARD
Failure to follow this warning could result in personal
injury or death.
Before performing service or maintenance operations on
unit, LOCKOUT/TAG-OUT the main power switch to unit.
Electrical shock and rotating equipment could cause severe
injury.
OUTSIDE
AIR
HOOD
FILTER
FILTER
CLIP
4

Supply Fan (Direct-Drive)

All JC units have the EcoBlue™ direct drive vane axial fan
system. The fan is driven by an ECM motor with speed that is
user set through the SystemVu™ controller. Speeds are fully
configurable from 40% to 100% of motor's maximum speed.
See Fig. 5 and 6.
MOTOR
PLUG
FAN
ROTOR
ECM
MOTOR
Fig. 5 — Direct-Drive Supply Fan Assembly
BLUE
YELLOW
3 2 1
BLACK
6 5 4
GRN/YEL
9 8 7
WHITE
ORANGE
GRAY
Fig. 6 — ECM Motor Plug Connectors
EVALUATING MOTOR SPEED
The direct drive ECM blower motor uses a constant speed de-
sign. Motor speed is controlled by a PWM signal sent from
SystemVu to directly control RPM.
Setting the Fan Speed with the SystemVu™ controls
The Fan Speed settings are accessed through the SystemVu
interface.
1. Check the job specifications for the CFM (cubic feet per
minute) and ESP (external static pressure) required.
2. Using the chart on the Fan Speed Set Up labels (see
Fig. 7), calculate the RPM from the CFM and ESP for the
base unit.
3. If installing any accessories listed at the bottom of the Set
Up Label, add accessory RPM to base unit RPM in upper
portion of label.
NOTE: The Fan Speed Set Up labels are located on the High Volt-
age cover in the Control Box.
4. Press any key on the SystemVu interface to activate the
display backlight and then press the MENU key.
Power L3 (3 phase only)
Power L2
Power L1
Earth Ground
CTL Signal Common
10vdc Source
PWM Signal