Checking Voltage; Checking Wiring; S-3A Thermostat And Wiring; S-3B Heating Anticipator - Goodman Amana AMH8 Service Instructions Manual

SERVICING
S-1 CHECKING VOLTAGE
HIGH VOLTAGE
D ALL
ISCONNECT POWER BEFORE SERVICING OR
CHANGING ANY ELECTRICAL WIRING.
F
SOURCES MAY BE PRESENT. AILURE TO DO SO MAY CAUSE
PROPERTY DAMAGE, PERSONAL INJURY OR DEATH.
1. Remove the burner door to gain entry to the Junc-
tion Box.
2. Remove cover from the Junction Box and gain ac-
cess to incoming power lines.
With Power ON:
WARNING
L
INE VOLTAGE NOW PRESENT
3. Using a voltmeter, measure the voltage across the
hot and neutral connections.
NOTE: To energize the furnace, the Door Interlock Switch
must be engaged at this point.
4. No reading - indicates open wiring, open fuse, no
power, or faulty Door Interlock Switch from unit to
fused disconnect service. Repair as needed.
5. With ample voltage at line voltage connectors, en-
ergize the furnace blower motor by jumpering ter-
minals R to G on the integrated ignition control.
6. With the blower motor in operation, the voltage
should be 115 volts ± 10 percent.
7. If the reading falls below the minimum voltage,
check the line wire size. Long runs of undersized
wire can cause low voltage. If wire size is ad-
equate, notify the local power company of the con-
dition.
8. After completing check and/or repair, replace
Junction Box cover and reinstall the service panel
doors.
9. Turn on electrical power and verify proper unit op-
eration.
S-2 CHECKING WIRING
WARNING
D ALL
ISCONNECT POWER BEFORE SERVICING.
1. Check wiring visually for signs of overheating, dam-
aged insulation and loose connections.
2. Use an ohmmeter to check continuity of any suspected
open wires.
50
WARNING
M
ULTIPLE POWER
3. If any wires must be replaced, replace with AWM,
105°C. 2/64 thick insulation of the same gauge or
its equivalent.
CHECKING THERMOSTAT, WIRING
AND ANTICIPATOR

S-3A THERMOSTAT AND WIRING

WARNING
D ALL
ISCONNECT POWER BEFORE SERVICING.
1. Remove the blower compartment door to gain ac-
cess to the thermostat low voltage wires located at
the furnace integrated control module terminals.
2. Remove the thermostat low voltage wires at the fur-
nace control panel terminal board.
3. Jumper terminals R to W on the integrated ignition
control.
With Power On (and Door Interlock Switch closed):
WARNING
L
INE VOLTAGE NOW PRESENT
4. Induced Draft Motor must run and pull in pressure
switch.
5. If the hot surface ignitor heats and at the end of
the ignitor warm-up period the gas valve opens
and the burners ignite, the trouble is in the ther-
mostat or wiring.
6. With power off, check the continuity of the ther-
mostat and wiring. Repair or replace as necessary.
If checking the furnace in the air conditioning mode,
proceed as follows.
7. With power off, Jumper terminals R to Y to G.
8. Turn on the power.
9. If the furnace blower motor starts and the con-
densing unit runs, then the trouble is in the ther-
mostat or wiring. Repair or replace as necessary.
10. After completing check and/or repair of wiring and
check and/or replacement of thermostat, reinstall
blower compartment door.
11. Turn on electrical power and verify proper unit op-
eration.

S-3B HEATING ANTICIPATOR

On older thermostats the heating anticipator is a wire
wound adjustable heater which is energized during the
"ON" cycle to help prevent overheating of the conditioned
space.