Lennox SLP99UHV Series Unit Information page 26

TABLE 9
Low Heat Blower Speeds
Thermostat
Blower
Demand
Speed
Adjustments
+ 15%
+ 7.5%
Low Heat
(R to W1)
Normal
- 7.5%
- 15%
Switches 14 through19 -- Heating Mode Blower Speed
-- Switches 14 through 19 are used to select heating mode
blower motor speeds. These switches are factory set at
the OFF position which provides 100 % of normal speed
during HIGH HEAT demand, 70% of normal speed during
MIDRANGE HEAT demand and 40% of normal speed
during LOW HEAT demand. Switches 14, 15 and 16 are
used to adjust the LOW FIRE blower motor speed. Switch-
es 17, 18 and 19 are used to adjust the HIGH FIRE blower
motor speed. FIGURE 6 and TABLE 9 and TABLE 10 pro-
vides the heating mode blower speeds that will result from
different switch settings. FIGURE 6 indicates the effect the
DIP switch settings have upon the heating airflow at vari-
ous furnace firing rates. Refer to blower tables at the front
of this manual for corresponding
cfm values.
Airflow Determination
Identify blower speed adjustment points at low and high fire
Airflow will lie on straight line between these two points and will fall within
the shaded area as shown
EXAMPLE -7.5% at low fire +7.5% at high fire
Increasing
Low Fire
Airflow
Dip Switches
14, 15, 16
+15%
+7.5%
Nominal
-7.5%
-15%
35%
DIP Switch Settings
14 15 16
On Off On
On Off Off
Off Off Off
On On Off
On On On
60%
50%
Thermostat
Blower Speed
Demand
High Heat
(R to W1 &
W2)
70% 80%
RATE (%)
FIGURE 6
Page 26
TABLE 10
High Heat Blower Speeds
DIP Switch Settings
Adjustments
17
+ 15% On
+ 7.5% On
Normal Off
- 7.5% On
- 15% On
High Fire
Dip Switches
17, 18, 19
90%
18 19
Off On
Off Off
Off Off
On Off
On On
+15%
+7.5%
Nominal
-7.5%
-15%
100%