Carrier 58HDX - Changing Blower Speed; Electrical Shock Hazard; Reduced Furnace Life Hazard; FURNACE MAINTENANCE

To check temperature rise,use the following procedure:
1.Place thermometers in supply and return air registers as close to
furnace as possible, avoiding direct radiant heat from heat
exchangers.
2.Operate furnace continuously for 15 minutes with all registers
and duct dampers open.
3.Take reading and compare with range specified on rating plate.
4.If the correct amount of temperature rise is NOT obtained, it
may be necessary to change blower speed. A higher blower speed
will lower the temperature rise. A lower blower speed will
increase the temperature rise.
Changing Blower Speed
ELECTRICAL SHOCK HAZARD
Failure to follow this warning could result in personal injury or
death.
Turn OFF power to furnace before changing speed taps.
NOTE: The speed taps that the manufacturer sets from the
factory for this product are based on a nominal 400 CFM per ton
cooling and the basic mid range on the temperature rise for
heating.
Since the manufacturer cannot establish the static pressure
that will be applied to the unit, it is the responsibility of the
installer dealer/contractor to select the proper speed taps for
the application when the unit is installed.
If it is necessary to change speeds, refer to steps below.
REDUCED FURNACE LIFE HAZARD
Failure to follow this caution may result in reduced furnace
life.
Use ONLY the blower motor speed taps insert indicated in
the Circulation Air Blower Data for setting air temperature
rise.
Table 8 — Blower Speed Chart
Wire Color Motor Speed
Black High
Orange* Med—High
Blue Medium
Red Low
* Med—High speed may not be provided on all models.
1. Refer to Furnace Wiring Diagram for location of the heat-
ing and cooling speed taps located on the furnace control
as well as location of unused blower motor speed leads.
Use the chart (Table 8) to determine the blower motor
speed settings.
2. Change the heat or cool blower motor speed by removing
the motor lead from the “Heat” or “Cool” terminal and
replace it with the desired motor speed lead from the
“Unused Motor Lead” location. Connect the wire previ-
ously removed from the “Heat” or “Cool” terminal to the
vacated “Unused Motor Lead” terminal.
3. If the same speed must be used for both heating and cool-
ing, remove the undesired motor speed lead from the
“Heat” or “Cool” terminal and connect that lead to the
open terminal at “Unused Motor Lead” location. Attach a
jumper between the “Heat” and “Cool” terminals and the
remaining motor speed lead.
NOTE: For motors with (4) speed leads, it will be necessary to
tape off the terminal of the motor speed lead removed from the
“Heat” or “Cool” terminal with electrical tape since an open
terminal will not be available at the “Unused Motor Lead”
location.
Continuous- Fan Operation using “G”
Energizing the “G” terminal on the furnace control provides
continuous fan operation. This is done by connecting the G
terminal of the thermostat to the G terminal on the furnace
control. When the FAN switch is turned from auto to ON the fan
will operate continuously at “HEAT” speed. EAC will be
energized in this mode.
NOTE: In heating, the fan will turn off during furnace ignition
and warm up then restart at heating speed.
Hard Wired Continuous Fan Operation
A terminal is provided on the furnace control board located in the
circulating blower compartment for operation of the continuous
fan option. This connection is intended for the low speed motor
tap, and has a lower contact rating (8 amps) than the heat and
cool taps. When the low speed blower lead is connected to this
terminal, this will provide low speed blower operation whenever
the other two speeds (Heat or Cool) are not energized.
Thoroughly check the system after modification to ensure the
proper operation of the circulating air blower in all modes of
operation.
Separate Speed Selections for Heat, Cool,
and Continuous Fan
Connect low speed lead from circulating motor to the “Cont.”
terminal at the furnace control. The appropriate motor leads
should already be connected to the “Heat” and “Cool” terminals.
Heating and Continuous Blower Speed the
Same
If it is necessary to operate the heating speed and continuous
blower speed using the same blower speed, connect a jumper
between the “Heat” and “Cont.” terminals on the furnace
control.
NOTE: There should be only ONE motor lead going to the
“Heat” and “Cont.” terminals.
FURNACE MAINTENANCE
FIRE, EXPLOSION, OR CARBON MONOXIDE
HAZARDS
Failure to follow this warning could result in personal injury,
death and/or property damage.
It is recommended that the furnace be inspected and serviced
on an annual basis (before the heating season) by a qualified
service technician.
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