Rheem GPT series Installation Instructions Manual page 31

SETTING BLOWER TIMINGS
The UT Electronic Controls control
boards have four quick connect
terminals for connecting the motor
speed leads. These are:
1. FAN — motor runs on this speed
when the thermostat is in the "FAN"
position.
2. COOL — connect desired cooling
speed.
3. HEAT — connect desired heating
speed.
4. HEAT/COOL* — connect desired
speed when heating and cooling
speed are the same.
CAUTION
DO NOT CONNECT ANY MOTOR
SPEEDS TO "HEAT" OR "COOL" IF
YOU USE THE "HEAT/COOL"
TERMINAL. DOING SO WILL
DAMAGE THE BLOWER MOTOR.
UNUSED MOTOR WIRE TAPS MUST
BE CONNECTED TO PARKING
TERMINALS M1 AND M2 OF THE IFC,
OR PROPERLY INSULATED.
5. If heating and continuous speed are
the same, jump across "FAN" and
"HEAT" terminals.
See Figure 22 for instructions for setting
the blower "OFF" timings.
GAS FURNACE (DIRECT
DRIVE) INSTRUCTIONS FOR
CHANGING BLOWER SPEED
WARNING
DISCONNECT THE ELECTRICAL
SUPPLY TO THE FURNACE BEFORE
ATTEMPTING TO CHANGE THE
BLOWER SPEED. FAILURE TO DO
SO CAN CAUSE ELECTRICAL
SHOCK RESULTING IN SEVERE
PERSONAL INJURY OR DEATH.
The blower motor is wired for blower
speeds required for normal operation
as shown.
If additional blower speed taps are
available (leads connected to "M1",
"M2" and "M3" on the electronic
control), speeds may be changed if
necessary to fit requirements of the
particular installation. Reconnect the
unused motor leads to "M1" or "M2."
Check motor lead color for speed
designation.
Heating speeds should not be reduced
where it could cause the furnace air
temperature to rise to exceed the
maximum outlet air temperature
specified for the unit.
IMPORTANT: Always check air
temperature rise after changing the
heating speed for any reason or if there
are any changes to the duct system.
WARNING
DO NOT CONNECT THE RED (1)
MOTOR WIRE TO EITHER THE
"HEAT" OR THE "H/C" TERMINALS.
DOING SO COULD DAMAGE THE
HEAT EXCHANGER AS THE
TEMPERATURE RISE WILL LIKELY
BE ABOVE THE PUBLISHED RANGE.
FIGURE 22
UT Electronic Controls
1028-930R
BLOWER OFF TIMINGS
ON
OFF
NOTE: SWITCH 3 IS USED FOR
TWINNING APPLICATIONS.
I402
OFF TIME SWITCH 1
90 SEC. OFF
120 SEC. OFF
160 SEC. ON
180 SEC. ON
IMPORTANT: Always check air
temperature rise after changing the
heating speed for any reason or if there
are any changes to the duct system.
SWITCH 2
ON
OFF
OFF
ON
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