Blower Speed Adjustment; Ramping Options; Cooling Mode Blower Speed Ramping - Lennox G71MPP SERIES Unit Information

Switches 10 and 11 −− Cooling Mode Blower Speed Ad-
justment −− Switches 10 and 11 are used to select blower
speed adjustment settings. The unit is shipped from the
factory with the DIP switches positioned for NORMAL (no)
adjustment. The DIP switches may be positioned to adjust
the blower speed by +10% or −10% to better suit the ap-
plication. The table below provides blower speed adjust-
ments that will result from different switch settings. Refer to
tables 1 through 11 for corresponding cfm values. With
switches 10 and 11 set to ON, motor will bypass ramping
profiles and all delays and immediately upon a call for cool,
run at COOLING speed selected. LED will continue to op-
erate as normal. This mode is used to check motor opera-
tion.
TABLE 18

Blower Speed Adjustment

Adjustment
+10% (approx.)
NORMAL (Factory)
−10% (approx.)
MOTOR TEST
Switches 12 and 13 −− Cooling Mode Blower Speed
Ramping −− Switches 12 and 13 are used to select cooling
mode blower speed ramping options. Blower speed ramp-
ing may be used to enhance dehumidification perfor-
mance. The switches are factory set at option A which has
the greatest effect on blower motor performance. Table 19
provides the cooling mode blower speed ramping options
that will result from different switch settings. The cooling
mode blower speed ramping options are detailed below.
TABLE 19

Cooling Mode Blower Speed Ramping

Ramping Option
A (Factory)
B
C
D
Switch 10 Switch 11
On Off
Off Off
Off On
On On
Switch 12 Switch 13
Off Off
On Off
Off On
On On
Ramping Option A (Factory Selection)
D Motor runs at 50% for 30 seconds.
D Motor then runs at 82% for approximately 7−1/2 min-
utes.
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.
OFF
1/2 MIN
50% CFM
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.
OFF
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.
OFF
Ramping Option D
S Motor runs at 100% until demand is satisfied.
S Once demand is met, motor ramps down to stop.
OFF
Page 21
7 1/2 MIN 100%
82% CFM CFM
COOLING DEMAND
Ramping Option B
7 1/2 MIN
100% CFM
82%CFM
COOLING DEMAND
Ramping Option C
100% CFM
100% CFM
45 SEC.
DEMAND
100% CFM
OFF
COOLING
DEMAND
OFF
1/2 MIN
50% CFM
OFF
OFF