3. Adjust temperature rise by adjusting blower speed. Increase blower speed to reduce temperature rise. Decrease blower speed to increase
temperature rise.
WARNING: ELECTRICAL SHOCK HAZARD
Failure to follow this warning could result in personal injury or death.
Disconnect 115-v electrical power before changing speed tap.
4. To change blower motor speed selections for heating mode, remove blower motor lead from control center HEAT terminal. (See Fig. 35.)
Select desired blower motor speed lead from 1 of the other motor leads and relocate it to HEAT terminal. See Table 18 for lead color
identification. Reconnect original lead on SPARE terminal.
Follow this same procedure for proper selection of COOL speed selection.
C.
Blower Off Delay (Heat Mode)
The blower off delay has 4 adjustable settings from 90 sec to 180 sec. (See Table 19.) The blower off delay jumpers are located on the furnace
control board (See Fig. 35). To change the blower off delay setting, move the jumper from one set of pins on the control board to the pins used
for the desired blower off delay. Factory blower off delay setting is 120 sec.
D.
Set Thermostat Heat Anticipator
When using a nonelectronic thermostat, the thermostat heat anticipator must be set to match amp draw of the electrical components in R-W circuit.
Accurate amp draw readings can be obtained at thermostat subbase terminals R and W. Fig. 65 illustrates an easy method of obtaining actual amp
draw. The amp reading should be taken after blower motor has started and furnace is heating. Connect ammeter wires as shown in Fig. 65. The
thermostat anticipator should NOT be in the circuit while measuring current. If thermometer has no subbase, the thermostat must be disconnected
from R and W wires during current measurement. See thermostat manufacturer’s instructions for adjusting heat anticipator and for varying heating
cycle length.
For an electronic thermostat, set cycle rate for 3 cycles per hour.
PROCEDURE 6—CHECK SAFETY CONTROLS
This section covers the safety controls that must be checked before installation is complete. The flame sensor, gas valve, and pressure switch were
all checked in the Start-up procedure section as part of normal operation.
Table 18—Speed Selector
COLOR
SPEED
FACTORY-SHIPPED
CONNECTION
Black
High
Cool
Yellow (When Present)
Medium High
Spare
Blue
Medium Low
Heat
Red
Low
Spare
White
Common
Com
Fig. 65—Amp Draw Check with Ammeter
A80201
R
Y W G
10 TURNS
THERMOSTAT SUBBASE
TERMINALS WITH
THERMOSTAT REMOVED
HOOK-AROUND
VOLT/AMMETER
EXAMPLE:
5.0 AMPS ON AMMETER
10 TURNS AROUND JAWS
= 0.5 AMPS FOR THERMOSTAT SETTING
FROM UNIT 24-VOLT
TERMINAL BLOCK
—66—
Summary of Contents for PG9MAA
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