Installation Guide

35
The cooling system manufacturer’s instructions must be checked
for required air flow. Any electronic air cleaners or other devices
may require specific air flows, consult installation instructions of
those devices for requirements.
3. Knowing the furnace model, locate the high stage cooling
air flow charts in the Specification Sheet applicable to
your model. Look up the cooling air flow determined in
step 2 and find the required cooling speed and adjustment
setting.
Example: A *MVC960603B* furnace installed with a 2.5
ton air conditioning system. The air flow
needed is 1000 CFM. Looking at the cooling
speed chart for *MVC960603B*, find the air
flow closest to 1000 CFM. A cooling airflow of
1007 CFM can be attained by setting the
cooling speed to “C”.
4. Continuous fan speeds that provide 25, 50, 75 and
100% of the furnace’s maximum airflow capability are
selectable via dip switches S5- 3, 4.
Example: If the furnace’s maximum airflow capability
is 2000 CFM and 25% continuous fan speed
is selected, the continuous fan speed will
be 0.25 x 2000 CFM = 500 CFM.
5. Locate the blower speed selection DIP (S3) switches on
the integrated control module. Select the desired “cooling”
speed tap by positioning switches 1 and 2 appropriately.
Select the desired “adjust” tap by positioning switches 3
and 4 appropriately. To enable adjustments and select -5,
5, -10 or 10% trim, you must set dip switch S5-2 to
ON. If S5-2 is in the OFF position , you will receive 0%
trim. Refer to the following figure for switch positions
and their corresponding taps. Verify CFM by noting the
number displayed on the dual 7-segment LED display.
6. The multi-speed circulator blower also offers several custom
ON/OFF ramping profiles. These profiles may be used to
enhance cooling performance and increase comfort level.
The ramping profiles are selected using DIP switches S4-
1, 2. Refer to the following figure for switch positions
and their corresponding taps. Refer to the following bullet
points for a description of each ramping profile. Verify
CFM by noting the number displayed on the dual 7-segment
LED display.
12
A* OFF OFF
BONOFF
COFFON
DONON
Switch Bank: S4
DIP Switch No.
(*Indicates factory setting)
Ramping
Profiles
• Profile A provides only an OFF delay of one (1) minute at
100% of the cooling demand airflow.
OFF
100% CFM 100% CFM
1 min
OFF
Figure 47
• Profile B ramps up to full cooling demand airflow by first
stepping up to 50% of the full demand for 30 seconds.
The motor then ramps to 100% of the required airflow. A
one (1) minute OFF delay at 100% of the cooling airflow is
provided.
50% CFM
1/2 min
100% CFM
100% CFM
1 min
OFF
OFF
Figure 48
• Profile C ramps up to 85% of the full cooling demand airflow
and operates there for approximately 7 1/2 minutes. The
motor then steps up to the full demand airflow. Profile C
also has a one (1) minute 100% OFF delay.
100% CFM
OFF
OFF
Figure 49
12
AOFFOFF
BONOFF
COFFON
D* ON ON
Sw itch Bank: S3
Cooling Speed
Taps
DIP Sw itch No.
(*Indicates factory setting)
34
+ 5%* OFF OFF
- 5% ON OFF
+ 10% OFF ON
- 10% ON ON
DIP Switch No.
(*Indicates factory setting)
Switch Bank: S3
Adjust Taps
NOTE: To enable adjustments and select -5, 5, -10 or 10%
trim, you must set dip switch S5-2 to ON. If S5-2 is in the
OFF position, you will receive 0% trim.