506887-01
Page 43 of 78
Issue 1213
These units are equipped with an integrated control. This
control manages ignition timing, combustion air inducer
speed, heating mode fan OFF delays and indoor blower
speeds based on selections made using the control DIP
switches and onboard links. The control includes an internal
feature which automatically resets the ignition control when
it has been locked out.
NOTE:
All DIP switches are factory shipped in the “OFF”
position.
Heating Operation DIP Switch Settings - Figure 41
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
DIIP switch must be repositioned. See Table 12.
Switch 2 - Operating Mode with Two Stage Thermostat
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. Conventional two
stage mode is the factory default setting. See Table 12.
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 12.
Switches 4 and 5 - Blower Off Delay -
The blower On delay
of 30 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 individual
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 settings
provide higher supply air temperatures. Table 13 provides
the blower Off timings that will result from different switch
settings.
Blower Off Delay Switch Settings
Table 16
Indoor Blower Operation DIP Switch Settings
Switches 6 and 7 - Continuous Indoor Fan Operation -
Blower Speed -
The unit is shipped from the factory with
the DIP switches positioned for medium low (38%) speed
during continuous indoor blower operation. Continuous fan
setting is 38% of cool setting and is not adjustable.
Thermostat Selection Switch Settings
Table 15
NOTE - When this furnace is used with a Comfort Sync
TM
communicating thermostat, all indoor blower speed
selections and DIP switch settings are made by the
communicating thermostat.
Summary of Contents for A97USMV
Page 3: ...506887 01 Page 3 of 78 Issue 1213 A97USMV Exploded View Figure 1 ...
Page 16: ...506887 01 Page 16 of 78 Issue 1213 Figure 17 ...
Page 28: ...506887 01 Page 28 of 78 Issue 1213 Trap Drain Assembly using 1 2 PVC or 3 4 PVC Figure 38 ...
Page 35: ...506887 01 Page 35 of 78 Issue 1213 ...
Page 36: ...506887 01 Page 36 of 78 Issue 1213 Figure 46 ...
Page 39: ...506887 01 Page 39 of 78 Issue 1213 ...
Page 40: ...506887 01 Page 40 of 78 Issue 1213 Typical A97USMV Wiring Diagram Figure 47 ...
Page 41: ...506887 01 Page 41 of 78 Issue 1213 Integrated Control Figure 48 ...
Page 42: ...506887 01 Page 42 of 78 Issue 1213 Low Voltage Field Wiring Table 14 2 Stage Single Stage ...
Page 46: ...506887 01 Page 46 of 78 Issue 1213 BLOWER DATA ...
Page 47: ...506887 01 Page 47 of 78 Issue 1213 BLOWER DATA ...
Page 48: ...506887 01 Page 48 of 78 Issue 1213 BLOWER DATA ...
Page 49: ...506887 01 Page 49 of 78 Issue 1213 BLOWER DATA ...
Page 50: ...506887 01 Page 50 of 78 Issue 1213 BLOWER DATA ...
Page 51: ...506887 01 Page 51 of 78 Issue 1213 BLOWER DATA ...
Page 52: ...506887 01 Page 52 of 78 Issue 1213 BLOWER DATA ...
Page 53: ...506887 01 Page 53 of 78 Issue 1213 BLOWER DATA ...
Page 54: ...506887 01 Page 54 of 78 Issue 1213 BLOWER DATA ...
Page 55: ...506887 01 Page 55 of 78 Issue 1213 TABLE 22 ...
Page 56: ...506887 01 Page 56 of 78 Issue 1213 TABLE 23 ...
Page 60: ...506887 01 Page 60 of 78 Issue 1213 Figure 50 ...
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