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TABLE 14
Thermostat Selection Switch Settings
Operation
Thermostat
Switch 1
Switch 2
Switch 3
Variable Capacity Heat
(40% to 100%)
Two−Stage
Off
On
Off
Three−Stage Heat
(40%, 70%, 100%)
Single−Stage
On
Off
2nd stage delay
OFF = 7 minutes
ON = 12 minutes
3rd stage delay
10 minutes fixed
Two−Stage Heat (W1 70%, W2 100%)
Two−Stage
Off
Off
Off
Heating Operation DIP Switch Settings −− Figure 4
Switch 1 −− Thermostat Selection −−
This unit may be used
with either a single−stage or two−stage thermostat. The
thermostat selection is made using a DIP switch which
must be properly positioned for the particular application.
The DIP switch is factory−positioned for use with a two−
stage thermostat. If a single−stage thermostat is to be used,
the DIP switch must be repositioned. See table 14.
Switch 2 −− Operating Mode with Two−Stage Thermo-
stat −−
If a two−stage thermostat is used, the furnace can
operate in either variable−capacity or conventional two−
stage mode. When variable−capacity mode is selected, the
firing rate of the unit is varied to maximize comfort. Conven-
tional two−stage mode is the factory default setting. See
table 14.
Switch 3 −− Second−Stage Heat On Delay −−
If a single−
stage thermostat is used, the integrated control can be
used to energize second−stage heat after either 7 minutes
or 12 minutes of first−stage heat operation. See table 14.
Switches 4 and 5 −− Blower−Off Delay −−
The blower−on
delay of 45 seconds is not adjustable. The blower−off delay
(time that the blower operates after the heating demand
has been satisfied) can be adjusted by moving switches 4
and 5 on the integrated control. The unit is shipped from the
factory with a blower−off delay of 90 seconds. The blower
off delay affects comfort and is adjustable to satisfy individ-
ual applications. Adjust the blower off delay to achieve a
supply air temperature between 90° and 110°F at the exact
moment that the blower is de−energized. Longer off delay
settings provide lower supply air temperatures; shorter set-
tings provide higher supply air temperatures. Table 15 pro-
vides the blower off timings that will result from different
switch settings.
TABLE 15
Blower Off Delay Switch Settings
Blower Off Delay
(Seconds)
Switch 4
Switch 5
60
Off
On
90
Off
Off
120
On
Off
180
On
On
Indoor Blower Operation DIP Switch Settings
Switches 6 and 7 −− Continuous Indoor Fan Operation −−
Blower Speed −
Switches 6 and 7 are used to select blower
motor speeds during continuous indoor blower operation.
The unit is shipped from the factory with DIP switches posi-
tioned for medium low (2) speed during continuous indoor
blower operation. The table below provides the continuous
blower speeds that will result from various switch settings.
Refer to tables 1 through 11 for corresponding cfm values.
TABLE 16
Continuous Indoor Fan
Speed
Switch 6
Switch 7
1 − Low (28%)
Off
On
2 − Medium Low
(38%)
(Factory)
Off
Off
3 − Medium High
(70%)
On
Off
4 − High (100%)
On
On
Switches 8 and 9 −− Cooling Mode Blower Speed −−
Switches 8 and 9 are used to select cooling blower motor
speed. The unit is shipped from the factory with the DIP
switches positioned for high speed (4) indoor blower motor
operation during the cooling mode. The table below pro-
vides the cooling mode blower speeds that will result from
different switch settings. Refer to tables 1 through 11 for
corresponding cfm values.
TABLE 17
Cooling Mode Blower Speeds
Speed
Switch 8
Switch 9
1 − Low
On
On
2 − Medium Low
Off
On
3 − Medium High
On
Off
4 − High (Factory)
Off
Off