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At times the light may appear to icker or glow. This takes 
place when the control is communicating with the motor 
between cycles. This is normal operation. 
Read through the jumper settings section before adjusting 
the jumper to obtain the appropriate blower speed. 
To change jumper positions, gently pull the jumper o the 
pins and place it on the desired set of pins. The following 
section outlines  the dierent  jumper  selections available 
and conditions associated with each one. Refer to gure 
11. 
After the CFM for each application has been determined, 
the jumper settings must be adjusted to reect those given 
in the blower tables. From the tables, determine which row 
most closely matches the desired CFM. Once a specic 
row has been chosen (+, NORMAL, or -), CFM volumes 
from other rows cannot be used. Below are descriptions of 
the jumper selections. 
The variable speed motor slowly ramps up to and down 
from the selected air ow during both cooling and heating 
demand. This minimizes noise and eliminates the initial 
blast of air when the blower is initially energized. 
ADJUST 
The ADJUST pins allow the motor to run at normal speed, 
approximately 15 percent higher, or approximately 15 
percent lower than normal speed. The blower data tables 
give three rows (+, NORMAL, and -) with their respective 
CFM volumes. Notice that the normal adjustment setting 
for  heat  speed  position  C in  table 1  is 900  CFM. The  + 
adjustment setting for that position is 1035 CFM and for 
the - adjustment setting is 765 CFM. After the adjustment 
setting has been determined, choose the remaining speed 
settings from those oered in the table in that row. 
The TEST pin is available to bypass the blower control 
and run the motor at approximately 70 percent to make 
sure that the motor is operational. This is used mainly in 
troubleshooting. The G terminal must be energized for the 
motor to run. 
COOL 
The COOL jumper is used to determine the CFM during 
cooling operation. This jumper selection is activated for 
cooling when Y1 is energized. The blower motor runs 
at  80  percent  of  the  selected  air  ow  for  the  rst  7-1/2 
minutes of each cooling demand. This feature allows for 
greater humidity removal and saves energy. In the cooling 
mode, the blower control board delays blower operation 
for 5 seconds after the compressor starts. The blower con-
tinues to operate for 90 seconds after the compressor is 
de-energized. 
HEAT 
The HEAT jumper is used to determine CFM during gas 
heat operation only. These jumper selections are activat-
ed only when W1 is energized. In the heating mode, the 
blower control board delays blower operation for 30 sec-
onds after the ame is established. The blower continues 
to operate for 90 seconds after the gas valve is de-ener-
gized. 
CONTINUOUS FAN 
When the thermostat is set for “Continuous Fan” operation 
and there is no demand for heating or cooling, the blower 
control will provide 50 percent of the COOL CFM selected. 
NOTE - With the proper thermostat and subbase, continu-
ous blower operation is possible by closing the R to G cir-
cuit. Cooling blower delay is also functional in this mode. 
DEHUMIDIFICATION 
The blower control board includes an HUM terminal which 
provides for connection of a humidistat. The JW1 resistor 
on the blower control board must be cut to activate the 
HUM terminal. The humidistat must be wired to open on 
humidity  rise.  When  the  dehumidication circuit  is used, 
the variable speed motor will reduce the selected air ow 
rate by 25 percent when humidity levels are high. An LED 
(D1) lights when the blower is operating in the dehumidi-
cation mode. 
NOTE - This unit is not approved for installation as part of 
a zoning system.