Page 8
Table 7. CBX25UHV‐048 Air Handler Performance (0 through 0.80 in. w.g. External Static Pressure Range)
ADJUST
Jumper
Setting
BDC3 Jumper Speed Positions
HEAT Speed
First-Stage COOL Speed
Second-Stage COOL Speed
1
2
3
4
1
2
3
4
1
2
3
4
cfm
cfm
cfm
cfm
cfm
cfm
cfm
cfm
cfm
cfm
cfm
cfm
+
1450
1670
1880
2340
1050
1200
1340
1650
1440
1670
1950
2340
NORM
1340
1520
1730
2100
950
1200
1230
1520
1325
1530
1740
2150
-
1210
1390
1570
1915
850
1000
1100
1375
1200
1380
1600
1950
NOTES - The effect of static pressure, filter and electric heater resistance is included in the air volumes listed.
First-stage cooling air volume is approximately 70% of the second-stage COOL speed setting.
. . . . . . . .
Continuous fan speed is approximately 50% of second-stage COOL speed setting.
. . . . . . . .
Lennox Harmony III
®
Zone Control Applications - Minimum air handler speed is approximately 450 cfm.
. . . . . . . .
Table 8. CBX25UHV‐060 Air Handler Performance (0 through 0.80 in. w.g. External Static Pressure Range)
ADJUST
Jumper
Setting
BDC3 Jumper Speed Positions
HEAT Speed
First-Stage COOL Speed
Second-Stage COOL Speed
1
2
3
4
1
2
3
4
1
2
3
4
cfm
cfm
cfm
cfm
cfm
cfm
cfm
cfm
cfm
cfm
cfm
cfm
+
1700
1930
2120
2275
1225
1410
1530
1690
1720
1930
2140
2270
NORM
1570
1760
1925
2100
1120
1260
1400
1540
1580
1765
1970
2100
-
1420
1595
1760
1920
1015
1160
1275
1390
1430
1625
1780
1890
NOTES - The effect of static pressure, filter and electric heater resistance is included in the air volumes listed.
First-stage cooling air volume is approximately 70% of the second-stage COOL speed setting.
. . . . . . . .
Continuous fan speed is approximately 50% of second-stage COOL speed setting.
. . . . . . . .
Lennox Harmony III
®
Zone Control Applications - Minimum air handler speed is approximately 450 cfm.
. . . . . . . .
Table 9. CBX25UHV, Thermostat and Single-Stage Outdoor Unit Operating Sequence
Operating Sequence
System Demand
System Response
System
Condition
Step
Thermostat Demand
Relative Humidity
Com
pressor
Air
Handler
CFM
(COOL)
Comments
Y1
Y2
O
G
W1
W2
Status
D
NO CALL FOR DEHUMIDIFICATION
Normal
Operation
1
On
On
On
Acceptable
24 VAC
High
100%
Compressor and indoor
air handler follow thermo
stat demand.
BASIC MODE (only active on a Y1 thermostat demand)
Normal
Operation
1
On
On
On
Acceptable
24 VAC
High
100%
Thermostat energizes Y1
and de-energizes D on a
call for dehumidification.
Dehumidification
Call
2
On
On
On
Demand
0 VAC
High
60%/65
70%*
PRECISION MODE (operates independent of a Y1 thermostat demand)
Normal
Operation
1
On
On
On
Acceptable
24 VAC
High
100%
Dehumidification mode
begins when humidity is
greater than set point.
Dehumidification
call
2
On
On
On
Demand
0 VAC
High
60%/65%
70%*
Dehumidification
call ONLY
1
On
On
On
Demand
0 VAC
High
60%/65%
70%*
Thermostat will try to
maintain room humidity
setpoint by allowing the
room space to maintain a
cooler room thermostat
setpoint.**
Jumpers at indoor unit with a single stage outdoor unit
With Condensing unit - Y1 to Y2 and R to O
With Heat Pump - Y1 to Y2
* During dehumidification, cooling air handler speed is as follows: 70% of second-stage COOL cfm for 018, 024, 030, 65% for 036 and 60% for 042, 048 and
060 units.
** Thermostat will maintain the room temperature up to 2°F (1.2°C) cooler than the room thermostat setting in precision mode.
