Indoor Blower Timing; Cooling Off - Delay Options - Trane *UH2B060A9V3VA Service Facts

Service Facts
2nd Stage satisfied, 1st Stage still called:
W2 Comfort Control contacts open signaling that 2nd Stage
Heating requirements are satisfied.
The induced draft blower is reduced to low speed allowing the
2nd Stage Pressure Switch contacts to open and the Gas
Valve is reduced to 1st Stage. The indoor blower motor is
reduced to low speed.
1st stage satisfied:
W1 Comfort Control contacts open signaling that 1st Stage
heating requirements are satisfied. The Gas Valve will close
and the induced draft blower will be de-energized. The indoor
blower motor will continue to run for the fan off period (Field
selectable at 60, 100, 140 or 180 seconds), then will be de-
energized by the control module.
Comfort Control call for heat (1-Stage Comfort Control)
W1/ W2 (jumpered) Comfort Control contacts close signaling
a call for heat. 1st Stage sequence of operation remains the
same as above. 2nd Stage Heat will energize after the Stage
delay timer (adjustable) has expired.
Comfort Control satisfied:
W1/ W2 (jumpered) contacts close signaling the control
module to close the Gas Valve. The induced draft blower is
switched to low speed and de-energized after the post purge
timer has expired. The indoor blower motor will continue to
operate after the flames are extinguished and then is
switched to low heat speed for the FAN-OFF period.

INDOOR BLOWER TIMING

▲
WARNING
!
SAFETY HAZARD
BODILY INJURY CAN RESULT FROM HIGH VOLTAGE
ELECTRICAL COMPONENTS, FAST MOVING FANS, AND
COMBUSTIBLE GAS. FOR PROTECTION FROM THESE
INHERENT HAZARDS DURING INSTALLATION AND
SERVICING, THE ELECTRICAL SUPPLY MUST BE
DISCONNECTED AND THE MAIN GAS VALVE MUST BE
TURNED OFF. IF OPERATING CHECKS MUST BE PER-
FORMED WITH THE UNIT OPERATING, IT IS THE
TECHNICIAN'S RESPONSIBILITY TO RECOGNIZE THESE
HAZARDS AND PROCEED SAFELY.
▲
CAUTION
!
The integrated furnace control is polarity sensitive. The hot
leg of the 115 VAC power must be connected to the BLACK
field lead.
Heating: The integrated furnace control module controls
the indoor blower. The blower start is fixed at 45 seconds
after ignition. The FAN-OFF period is field selectable by
dip switches SW-2, #1 and #2 at 60, 100, 140, or 180
seconds. The factory setting is 100 seconds.
W1-W2 stage delay (jumpered together) is field selectable by
dip switch SW-1, #1 and #2 at .5, 5, 10 or 15 minutes. The
factory setting is 10 minutes. (See wiring diagram).
Cooling: The fan delay-off period is set by dip switches on the
Integrated Furnace Control. The options for cooling delay off
is field selectable by dip switches #5 and #6.
6
Table 1 and Figure 1 explain the delay-off settings:

COOLING OFF - DELAY OPTIONS

SWITCH SETTINGS
5 - OFF 6 - OFF
5 - ON 6 - OFF
5 - OFF 6 - ON
5 - ON 6 - ON
* - This setting is equivalent to BAY24X045 relay benefit
** - This selection provides ENHANCED MODE, which is a
ramping up and ramping down of the blower speed to provide
improved comfort, quietness, and potential energy savings.
See Wiring Diagram notes on the unit or in the Service Facts
for complete wiring setup for ENHANCED MODE. The graph
which follows, shows the ramping process.
80%
Dehumidify
50%
Fast Coil Cooling
OFF
1 7.5
minutes
minute
Figure 1
Table 1
NOMINAL
SELECTION
AIRFLOW
NONE SAME
1.5 MINUTES 100% *
3 MINUTES 50%
** 50 - 100%
100% if necessary
50%
Efficiency
3
minutes
X343070P08
OFF