SERVICING
63
1. Disconnect power to air handler or modular blower.
NOTE:
Motor contains capacitors that can hold a charge for
several minutes after disconnecting power. Wait 5 minutes
after removing power to allow capacitors to discharge.
2. Disassemble motor as described in steps 2 through 4
above.
3. Locate the 3-circuit harness from the motor. Using an
ohmmeter, measure the resistance between each motor
phase winding. The resistance levels should be equal.
Replace the motor if the resistance levels are unequal,
open circuited or short circuited.
4. Measure the resistance between each motor phase
winding and the motor shell. Replace the motor if any
phase winding is short circuited to the motor shell.
5. Reassemble motor and control/end bell in reverse of
disassembly. Replace blower assembly into air handler
or modular blower.
S-16H ECM CFM ADJUSTMENTS DVPTC/MBVC
This section references the operation characteristics of the
DVPTC/MBVC models. The MBVC models utilize an
integrated air handler control. The air handler control
provides ECM blower motor control and includes all
dipswitches necessary to set up the cooling, heat pump and
electric airflow characteristics.
The control has three banks of dipswitches: a bank for
cooling airflow and trim adjustment, a bank for selecting one
of (4) enhancement profiles and enabling dehumidification,
and a bank for selecting the installed electric heater kit size.
Adjustments are made by selecting the appropriate ON/
OFF combinations of the dipswitches. The dipswitches
along with their functions are shown in the figures below.
Cooling Airflow Dipswitches
- Used to set the desired
cooling airflow
Cooling Airflow Speed Tap (* indicates factory setting)
Tap A
1
OFF ON
2
Tap B
1
OFF ON
2
Tap C
1
OFF ON
2
Tap D*
1
OFF ON
2
Airflow Adjust Dipswitches
- Used to adjust the a/-
10%
Airflow Adjust Taps (* indicates factory sett ing)
Normal*
3
OFF ON
4
+10%
3
OFF ON
4
- 10%
3
OFF ON
4
Normal
3
OFF ON
4
Ramping Profile Dipswitches
- Used to select a comfort
profile for the cooling mode.
Cooling Airflow Ramping Profiles (* indicates factory
setting)
Tap A*
5
OFF ON
6
Tap B
5
OFF ON
6
Tap C
5
OFF ON
6
Tap D
5
OFF ON
6
Dehumidification Disable/Enable Dipswitch
- Reduces cool-
ing airflow by ~ 15% when enabled AND when used with a
humidistat (such as DEHUM1). Airflow is reduced when a
call for cooling is present and the humidistat is open.
7
8
OFF ON
DEHUM
Unused
Move to the ON position to
enable dehumidification
Electric Heater Airflow
- Airflow for installed electric heaters
is set by adjusting the dipswitches to the appropriate heater
size.
Electric Heating Airflow (* indicates factory setting)
21 kW*
9
OFF ON
10
11
20 kW
9
OFF ON
10
11
15 kW
9
OFF ON
10
11
10 kW
9
OFF ON
10
11
8 kW
9
OFF ON
10
11
6 kW
9
OFF ON
10
11
5 kW
9
OFF ON
10
11
3 kW
9
OFF ON
10
11
Electric Heating Airflow (* indicates factory setting)
The table on the following page indicates the airflow that
corresponds to the available dipswitch settings.