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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.
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