Lennox SL280DFV Installation Instructions Manual page 33

NOTE − The off portion of the selected ramp profile also ap-
plies during heat pump operation in dual fuel applications.
TABLE 17
Cooling Mode Blower Speed Ramping
Ramping Option
A (Factory)
B
C
D
Ramping Option A (Factory Selection)
D Motor runs at 50% for 30 seconds.
D Motor then runs at 82% for approximately 7−1/2 minu-
tes.
D If demand has not been satisfied after 7−1/2 minutes,
motor runs at 100% until demand is satisfied.
D Once demand is met, motor runs at 50% for 30 sec-
onds then ramps down to stop.
7 1/2 MIN
OFF
82% CFM
1/2 MIN
50% CFM
COMPRESSOR DEMAND
Ramping Option B
S Motor runs at 82% for approximately 7−1/2 minutes. If
demand has not been satisfied after 7−1/2 minutes,
motor runs at 100% until demand is satisfied.
S Once demand is met, motor ramps down to stop.
7 1/2 MIN
OFF 82%CFM
COMPRESSOR DEMAND
Ramping Option C
S Motor runs at 100% until demand is satisfied.
S Once demand is met, motor runs at 100% for 45 sec-
onds then ramps down to stop.
100% CFM
OFF
COMPRESSOR
DEMAND
Switch 9 Switch 10
Off Off
Off On
On Off
On On
100%
OFF
CFM
1/2 MIN
50% CFM
100% CFM
100% CFM
45 SEC.
Ramping Option D
S Motor runs at 100% until demand is satisfied.
S Once demand is met, motor ramps down to stop.
OFF
Switches 11, 12 and 13 −− Heating Mode Blower Speed −−
The switches are factory set to the OFF position which pro-
vides normal heat speed. Refer to table 18 for switches 11,
12 and 13 that provided the corresponding increases or de-
crease to both high and low heat demand.
Heating Mode Blower Speeds
Heat Speed
Increase 24%
Increase 18%
Increase 12%
Increase 6%
Factory Default
Decrease 6%
Decrease 12%
Decrease18%
Switches 14 and 15 −− Continuous Blower Speed −−
Table 19 provides continuous blower speed adjustments
that will result from different switch settings.
OFF
Continuous Blower Speed
Continuous
Blower Speed
28% of High Cool Speed
38% of High Cool Speed
(Factory)
70% of High Cool Speed
OFF
100% of High Cool Speed
Page 33
100% CFM
OFF
COMPRESSOR
DEMAND
TABLE 18
Switch Switch Switch
11 12
On On
On On
On Off
On Off
Off Off
Off Off
Off On
Off On
TABLE 19
Switch 14 Switch 15
Off
Off
On
On
13
On
Off
On
Off
Off
On
Off
On
On
Off
Off
On