507787-01
Issue 2007
Page 16 of 22
Change Blower Speed
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 blue wire.
4.
Select the required blower motor speed. Connect red-
LO or black-HI and plug it into the 4-pin blower relay
harness connector.
NOTE:
Reuse the factory-installed rubber wire cap on
the unused wires.
5.
Replace all panels.
6.
Reconnect power.
NOTE:
To change blower speed on Constant Torque
-048 and -060 units, remove the wire from terminal
Y1 on the strip and install on either of the speeds not
being used (Brown TAP 2 or Black TAP 5).
Air Flow – Cooling Blower Speed
The cooling blower speed is factory configured to provide
correct air flow for an outdoor unit that matches the 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 in Table 4.
Electric shock hazard! - Disconnect all power
supplies before servicing.
Replace all parts and panels before operating.
Failure to do so can result in death or electrical
shock.
WARNING
2
BLUE (MED)
RED (L0)
BLACK (HI)
YELLOW (COM)
5
BLOWER RELAY
BLOWER RELAY
PLASTIC CAPS
4-PIN
BLOWER CONNECTOR
HARNESS
NOTE - Refer to wiring diagram located on the
unit
ance (table 2).
All air data measured external to unit with 1
inch non-pleated air filter in place.
All factory settings are medium speed.
All data given while air handler is operating
with a dry DX evaporator coil.
All downflow applications run on high speed
when utilizing electric heat.
Figure 18. Changing Blower Speed
