Installation Manual

Specifications subject to change without notice.
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will transition to or bring on the blower motor BLWM at
cooling airflow, low-- heat airflow, or the mid--range airflow,
whichever is lowest. The blower motor BLWM will remain
on until the main burners ignite then shut OFF and remain
OFF for 25 sec before coming back on at heating airflow.
When the W/W1 input signal disappears, the furnace con-
trol begins a normal inducer post-- purge period while
changing the blower airflow. If Y/Y2 input is still energized
the furnace control CPU will transition the blower motor
BLWM airflow to cooling airflow. If Y/Y2 input signal dis-
appears and the Y1 input is still energized the furnace con-
trol CPU will transition the blower motor BLWM to low--
cooling airflow. If both the Y1 and Y/Y2 signals disappear
at the same time, the blower motor BLWM will remain on at
low--heat airflow for the selected blower--OFF delay period.
At the end of the blower-- OFF delay, the blower motor
BLWM will shut OFF unless G is still energized, in which
case the blower motor BLWM will operate at continuous
blower airflow.
Component Self--Test
Refer to “Component Self Test” in the Serv ice and Maintenance
section for details.