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On−Board Jumper W914
On−board jumper W914, which connects terminals DS and
R on the integrated control board, must be cut when the fur-
nace is installed with a thermostat which features humidity
control.
On−Board Jumper W951
On−board jumper W951, which connects terminals R and O
on the integrated control board, must be cut when the fur-
nace is installed in applications which include a heat pump
unit and a thermostat which features dual fuel use. If the
jumper is left intact, terminal O" will remain energized elim-
inating the HEAT MODE in the heat pump.
On−Board Jumper W915
On−board jumper W915, which connects terminals Y1 and
Y2 on the integrated control board, must be cut if two−stage
cooling will be used. If the jumper is not cut the outdoor unit
will operate in first−stage cooling only.
Status LEDs (HI/LO, CFM, ANI)
The green HI/LO LED indicates circulating blower speed in
response to the DS signal. The LED is lit during normal
blower operation and is off during a dehumidification de-
mand.
The green CFM LED indicates the blower air flow. Count
the number of blinks between the two−second pauses to
determine the airf low. Each blink represents approximate-
ly 50 L/s (100CFM).
The red ANI LED flashes diagnostic codes, which are de-
tailed on page 43.
Indoor Fan Operation DIP Switch Settings
Switches 1 and 2 −− Blower Speed Adjustment −−
Switches 1 and 2 are used to select blower speed adjust-
ment 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 application. The
table below provides blower speed adjustments that will re-
sult from different switch settings. Refer to tables 14
through NO TAG for corresponding cfm values.
TABLE 10
Blower Speed Adjustment
Adjustment
Switch 1
Switch 2
+10% (approx.)
On
Off
NORMAL (Factory)
Off
Off
−10% (approx.)
Off
On
Switches 3 and 4 −− Cooling Mode Blower Speed −−
Switches 3 and 4 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 14 through
NO TAG for corresponding cfm values.
TABLE 11
Cooling Mode Blower Speeds
Speed
Switch 3
Switch 4
1 − Low
On
On
2 − Medium Low
Off
On
3 − Medium High
On
Off
4 − High (Factory)
Off
Off
Switches 5 and 6 −− Cooling Mode Blower Speed Ramp-
ing −−
Switches 5 and 6 are used to select cooling mode
blower speed ramping options. Blower speed ramping may
be used to enhance dehumidification performance. The
switches are factory set at option A which has the greatest
effect on blower motor performance. Table 12 provides the
cooling mode blower speed ramping options that will result
from different switch settings. The cooling mode blower
speed ramping options are detailed on the next page.
NOTE − The off portion of the selected ramp profile also ap-
plies during heat pump operation in dual fuel applications.
TABLE 12
Cooling Mode Blower Speed Ramping
Ramping Option
Switch 5
Switch 6
A (Factory)
Off
Off
B
On
Off
C
Off
On
D
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 minu-
tes.
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
OFF
1/2 MIN
50% CFM
COOLING DEMAND
7 1/2 MIN
82% CFM
100%
CFM
1/2 MIN
50% CFM
Ramping Option B
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
OFF
82%CFM
100% CFM
COOLING DEMAND
7 1/2 MIN
Ramping Option C
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.
