Goodmans DSZ User Manual
SERVICING
46
S-16C CHECKING ECM MOTOR WINDINGS
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.
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.
1. Disconnect the 5-pin and the 16-pin connectors from the
ECM power head.
2. Remove the 2 screws securing the ECM power head and
separate it from the motor.
3. Disconnect the 3-pin motor connector from the power
head and lay it aside.
4. Using an ohmmeter, check the motor windings for con-
tinuity to ground (pins to motor shell). If the ohmmeter
indicates continuity to ground, the motor is defective and
must be replaced.
indicates continuity to ground, the motor is defective and
must be replaced.
5. Using an ohmmeter, check the windings for continuity
(pin to pin). If no continuity is indicated, the thermal limit
(over load) device may be open. Allow motor to cool and
retest.
(over load) device may be open. Allow motor to cool and
retest.
16-pin
connector
connector
5-pin
connector
connector
3-pin motor
connector
connector
S-16D ECM CFM ADJUSTMENTS MBE / AEPF
MBE MOTOR
This section references the operation characteristics of the
MBE/AEPF models motor only. The ECM control board is
factory set with the dipswitch #4 in the “ON” position and all
other dipswitches are factory set in the “OFF” position. When
MBE/AEPF are used with 2-stage cooling units, dipswitch
#4 should be in the "OFF" position.
MBE/AEPF models motor only. The ECM control board is
factory set with the dipswitch #4 in the “ON” position and all
other dipswitches are factory set in the “OFF” position. When
MBE/AEPF are used with 2-stage cooling units, dipswitch
#4 should be in the "OFF" position.
For most applications, the settings are to be changed
according to the electric heat size and the outdoor unit
selection.
according to the electric heat size and the outdoor unit
selection.
The MBE/AEPF products use a General Electric ECM
TM
motor. This motor provides many features not available on
the traditional PSC motor. These features include:
the traditional PSC motor. These features include:
•
Improved Efficiency
•
Constant CFM
•
Soft Start and Stop
•
Improved Humidity Control
MOTOR SPEED ADJUSTMENT
Each ECM™ blower motor has been preprogrammed for
operation at 4 distinct airflow levels when operating in
Cooling/Heat Pump mode or Electric Heat mode. These 4
distinct levels may also be adjusted slightly lower or higher
if desired. The adjustment between levels and the trim
adjustments are made by changing the dipswitch(s) either
to an "OFF" or "ON" position.
operation at 4 distinct airflow levels when operating in
Cooling/Heat Pump mode or Electric Heat mode. These 4
distinct levels may also be adjusted slightly lower or higher
if desired. The adjustment between levels and the trim
adjustments are made by changing the dipswitch(s) either
to an "OFF" or "ON" position.
DIPSWITCH FUNCTIONS
The MBE / AEPF air handler motors have an electronic
control that contains an eight (8) position dip switch. The
function of these dipswitches are shown in Table 1.
control that contains an eight (8) position dip switch. The
function of these dipswitches are shown in Table 1.
D ipsw itch N um ber
Function
1
2
3
2
3
N /A
4
Indoor Therm ostat
5
6
7
8
6
7
8
C oo ling & H eat Pum p C FM
C FM Trim Adjust
Electric H eat
Table 1
CFM DELIVERY
Tables 2, 3, 5 and 6 show the CFM output for dipswitch
combinations 1-2, and 5-6.
combinations 1-2, and 5-6.
Model
Switch 1
Switch 2
CFM
OFF
OFF
1,200
ON
OFF
1,000
OFF
ON
800
ON
ON
600
OFF
OFF
1,600
ON
OFF
1,400
OFF
ON
1,200
ON
ON
1,000
OFF
OFF
2,000
ON
OFF
1,800
OFF
ON
1,600
ON
ON
1,200
MBE1200
MBE1600
MBE2000
Electric Heat Operation
Table 2