Lennox CBX32MV Installation Instructions Manual page 34

Cooling Operation
Air Handler Control AHC) Indoor Blower Mode Speed and Profiles settings
1. Set Cooling Mode Blower Speed jumper pin.
2. Set Cooling Mode Blower Ramping jumper pin.
3. Set Blower Adjust Selection jumper pin.
Single or Two−Stage Unit
AHC on−board link must be cut between Y1 and Y2 to allow 2 stage
cooling operation.
Air Handler Control (AHC) receives inputs on Y1 terminal
Y1 terminal on AHC is configured as input and passes signal
from room thermostat to outdoor unit.
NOTE − The outdoor unit control directly controls the outdoor
unit operation.
Y1 input to the AHC will control the indoor blower according to the cooling or
heating mode blower speed, ramping and adjust selection jumper pins.
Room thermostat calls for
second stage?
Yes
Y2 terminal on AHC is
configured as input and passes
signal from room thermostat to
outdoor unit.
NOTE − The outdoor unit
control directly controls the
outdoor unit operation.
Still calling for second
stage?
RECOMMEND
JUMPER CONFIGURATIONS ON THE AIR HANDLER CONTROL.
Room thermostat
calls for first
stage?
.
Yes
Y2 terminal is an
input to the AHC.
The indoor blower
will be controlled
according to the
jumper pin
selections.
Yes
No
CUT ON−BOARD LINK Y1−Y2 FOR
TWO−STAGE A/C
USE FIGURE 21 AS A REFERENCE FOR SETTING
IMPORTANT − Use care when cutting links to prevent damage to
control. See figure 21, CBX32MV jump and link guide for further
details.
Yes
No
De−energize Y2 terminal on AHC. Indoor
blower speed will reset to Y1 demand.
NOTE − The outdoor unit control directly
controls the outdoor unit operation.
De−energize Y1 (and O in cooling) terminal
on AHC.
NOTE − The outdoor unit control directly
controls the outdoor unit operation.
De−energize indoor blower per ramping
Page 34
Still calling for first
Yes
stage?
No
profile.
Y1−Y2
2−STAGE
COMPR
R−O
HEAT
PUMP
R−DS
DEHUM
OR
HARMONY