Fan Motor Connector Check For Ftq-Ta - Daikin SkyAir RZR-TA Series Service Manual

Check

5.15 Fan Motor Connector Check for FTQ-TA

CHECK 19
CHECKING EMERSON ULTRATECH
The FTQ-TA models utilize an Emerson, 4-wire variable speed ECM blower motor. The ECM
blower motor provides constant CFM.
The motor is a serially communicating variable speed motor. Only four wires are required to control
the motor: +Vdc, Common, Receive, and Transmit.
The +Vdc and Common wires provide power to the motor's low voltage control circuits.
General Checks / Considerations
1. Check power supply to the air handler or modular blower. Ensure power supply is within the
2. Check motor power harness. Ensure wires are continuous and make good contact when seated
3. Check motor control harness. Ensure wires are continuous and make good contact when
4. Check blower wheel. Confirm wheel is properly seated on motor shaft. Set screw must be on
5. Ensure motor and wheel turn freely. Check for interference between wheel and housing or
6. Check housing for cracks and/or corrosion. Repair or replace as needed.
7. Check motor mounting bracket. Ensure mounting bracket is tightly secured to the housing.
Emerson UltraCheck-EZ
The Emerson UltraCheck-EZ
Warning
HIGH VOLTAGE!
Disconnect ALL power before servicing or installing. Multiple power sources may be present.
Failure to do so may cause property damage, personal injury or death.
To use the diagnostic tool, perform the following steps:
1. Disconnect power to the air handler.
2. Disconnect the 4-circuit control harness from the motor.
3. Plug the 4-circuit connector from the diagnostic tool into the motor control connector.
4. Connect one alligator clip from the diagnostic tool to a ground source.
5. Connect the other alligator clip to a 24VAC source.
6. Turn on power to air handler or modular blower.
Warning
Line Voltage now present.
7. Depress the orange power button on the diagnostic tool to send a run signal to the motor. Allow
up to 5 seconds for the motor to start.
NOTE: If the orange power button does not illuminate when depressed, the tool either has an open
fuse or is not properly connected to a 24VAC source.
8. The green LED on the diagnostic tool will blink indicating communications between the tool and
motor. See table below for indications of tool indicators and motor actions. Replace or repair as
needed.
280
range specified on rating plate.
in the connectors. Repair or replace as needed.
seated in the connectors. Repair or replace as needed.
shaft flat and torqued to 165 in-lbs minimum. Confirm wheel has no broken or loose blades.
Repair or replace as needed.
wheel and motor. Repair or replace as needed.
Ensure bracket is not cracked or broken.
TM
Diagnostic Tool
TM
NOTE: The alligator clips are NOT polarized.
NOTE: The UltraCheck-EZ
Connecting the tool to a source other than 24VAC could damage the tool and cause the fuse to
open. Doing so will render the diagnostic tool inoperable.
TM
ECM MOTORS
diagnostic tool may be used to diagnose the ECM motor.
TM
diagnostic tool is equipped with a nonreplaceable fuse.
SiUS281811E
Part 6 Service Diagnosis