Carrier Idrofan 42NH, Installation, Operating And Maintenance Instruction

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4 - COMPONENTS AND MAINTENANCE
4.1 - Fan motor assembly
4.1.1 - Fan assembly removal procedure
WARNING: Disconnect the power supply to the unit
before carrying out any work on the unit.
Identify and note the wired fan speeds. If the fan
develops a fault the whole assembly must be removed
and replaced (Fig. 12).
■ Remove the filter.
■ Remove the fan access panel.
■ Disconnect the fan assembly power supply cables
(power and control wiring for variable-speed motor).
■ If necessary remove the controller (fixed with screws)
to gain access to the maintenance screws of the
panel supporting the fan.
■ The fan assembly and its panel are held in place by
four screws. Remove these screws and slide the
assembly down.
■ Remove the fan motor assembly.
NOTE: Be careful not to touch the fan blades during
the removal process to avoid unbalancing the fans.
■ For units with the electric heater option, disconnect
the power supply cable to the heater. Withdraw the
cable through the cable gland.
■ Unscrew the electric heaters.
■ Replacement of the fan motor assembly is by the
reversal of the above procedure.
WARNING: The electrical connections to the fan
motor must be made in accordance with the labels
on the connector block
4.1.2 - Capacitor replacement procedure
Disconnect the power supply to the unit before
carrying any work on the unit.
■ Remove the filter.
■ Remove the fan motor assembly access panel.
■ Remove the capacitor that is attached to the motor
chassis assembly.
■ Disconnect the capacitor by withdrawing the flat
spade connectors from the back of the capacitor.
■ Replacement of the capacitor assembly is by the
reversal of the above procedure.
4.1.3 - Fan wiring
For any modifications of the wiring harness, refer to the
fan wiring diagrams provided with the units.
With the optional electrical box, three of the available
five or six speeds of AC motor are connected -
(maximum speed = R1, minimum speed = R5 for 42NH
/R6 for 42NL).
When the unit is delivered with an WTC or a NTC
controller, for AC motor, three of the 5 or 6 speeds are
connected. Speeds arrangement can be changed on
site according to the electrical diagram.
WARNING: With the optional electric heater a
minimum air flow must be maintained (see tables
below).
Damages may occur if the minimal speed
recommendation is not followed.
Minimum speed 42NH / (Minimum air flow in m
3
/h)
Size
Multispeed AC Motor With Elec. Heater
0-1000W 1600-2000W 3200W
2_5 R5 (70 m
3
/h)
NA NA
3_5 R5 (180 m
3
/h)
NA
4_5 R5 (340 m
3
/h)
NA
5_5 R5 (300 m
3
/h)
NA
6_5 R5 (300 m
3
/h)
7_5
R5 (460 m
3
/h)
Minimum speed 42NH / (Minimum air flow in m
3
/h)
Size
EC Motor With Elec. Heater
0-1000W 1500-2400W 3000-3200W
2_9 3V (70 m
3
/h)
NA NA
3_9 3V (180 m
3
/h)
NA
4_9 3V (275m
3
/h)
NA
5_9 3V (300 m
3
/h)
NA
6_9 3V (180 m
3
/h)
7_9
3V (300 m
3
/h)
Minimum speed 42NL / (Minimum air flow in m
3
/h)
Size
Multispeed AC Motor With Elec. Heater
0-1000W 1600-2000W 3200W
2_5 R6 (70 m
3
/h)
NA NA
3_5 R6 (180 m
3
/h)
NA
4_5 R6 (340 m
3
/h)
NA
5_5 R6 (300 m
3
/h)
NA
Minimum speed 42NL / (Minimum air flow in m 3 /h)
Size
EC Motor With Elec. Heater
0-1000W 1500-2400W 3000-3200W
2_5 3V (70 m
3
/h)
NA NA
3_5 3V (180 m
3
/h)
NA
4_5 3V (275 m
3
/h)
NA
5_5 3V (300 m
3
/h)
NA
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