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505059M 0511
R
G
CONDENSING
UNIT
R
R
R
G
G
G
BU
BU
W
W
W
BK
BK
COOLING-ONLY APPLICATION
AIR HANDLER
THERMOSTAT
HEAT-ONLY APPLICATION
AIR HANDLER
THERMOSTAT
CONDENSING
UNIT
COOLING APPLICATION WITH
ELECTRIC HEAT
AIR HANDLER
THERMOSTAT
HEAT PUMP APPLICATION WITH ELECTRIC HEAT
AIR HANDLER
THERMOSTAT
HEAT PUMP UNIT
NOTE − Connect common wire only if required (Refer to the appropriate thermostat installation instructions)
BU
BU
SEE
NOTE
SEE
NOTE
SEE
NOTE
SEE
NOTE
Figure 14. Low Voltage Connections
Airflow Cooling Blower Speed
The cooling blower speed is factory configured to provide
correct airflow for an outdoor unit that matches the
maximum cooling capacity rating of the air handler.
If the outdoor unit is smaller than the maximum cooling
capacity rating for the air handler, the cooling blower speed
may need to be changed. Refer to Blower Performance
Chart, table 4.
CHANGE BLOWER SPEED
NOTE Refer to wiring diagram (figure 13) and blower
performance (table 4).
WARNING
Electric shock hazard! − Disconnect all
power supplies before servicing.
Replace all parts and panels before op-
erating.
Failure to do so can result in death or elec-
trical shock.
1. Disconnect all power supplies.
2. Remove the air handler access panel.
3. Locate pin number 2 on the blower relay. Two black
wires are connected to this terminal pin. One connects
to pin number 5 on the blower relay, one connects to
an in−line splice connecting to a red wire.
4. Remove the wire going to the 4−pin blower motor
connector from the splice.
5. Connect the blower lead [Red (LO), Black (HI)] onto
the splice from the 4−pin blower motor connector.
NOTE Reuse the factory−installed plastic cap on
whichever wire is not used.
6. Replace all panels.
7. Reconnect power.
NOTES FOR TABLE 4 −
All air data measured external to unit with 1
inch non−pleated air filter in place.
Electric heaters have no appreciable air resistance.
All factory settings are high−speed.
All data given while air handler is operating with a dry dx coil.
