Checking Hot Surface Ignitor - Goodman ACS series Service Instructions Manual

SERVICING
Propane Gas Adjustments
HIGH VOLTAGE
D ALL
ISCONNECT ELECTRICAL POWER AND SHUT OFF GAS
SUPPLY BEFORE SERVICING OR INSTALLING THIS UNIT.
M
ULTIPLE POWER SOURCES MAY BE PRESENT.
DO SO MAY CAUSE PROPERTY DAMAGE, PERSONAL INJURY OR DEATH.
1. After turning off gas to furnace at the manual gas shutoff
valve external to the furnace, remove burner compart-
ment door to gain access to the gas valve.
2. Connect a calibrated water manometer (or appropriate
gas pressure gauge) at the gas valve outlet pressure
tap. Refer to previous Measuring Manifold Gas Pressure
figure for proper connection.
WARNING
L
INE VOLTAGE NOW PRESENT
3. Turn ON the gas and electrical power supply and oper-
ate the furnace.
4. Remove the cap screw from the low stage manifold pres-
sure regulator.
5. Using a 3/32" Allen wrench, increase low fire manifold
pressure by adjusting the low stage manifold regulator
so the furnace will light and carryover.
6. Remove the cap screw from the high stage manifold pres-
sure regulator adjustment location.
7. Using a 3/32" Allen wrench, adjust the high stage mani-
fold pressure regulator to the required manifold pressure.
8. Reinstall high stage manifold regulator cap screw. Re-
check manifold pressure setting with cap on.
9. Using a 3/32" Allen wrench, adjust the low stage mani-
fold pressure regulator to the required manifold pressure.
10. Reinstall low stage manifold cap screw and recheck mani-
fold pressure setting with cap on.
HIGH VOLTAGE
D ALL
ISCONNECT ELECTRICAL POWER AND SHUT OFF GAS SUPPLY
BEFORE SERVICING OR INSTALLING.
11. Disconnect manometer after turning off gas at manual
shutoff valve. Reinstall gas valve outlet pressure tap plug
before turning on gas to furnace.
12. Turn on gas to furnace and check for leaks. If leaks are
found, repair and then reinstall burner compartment door.
122
WARNING
F
AILURE TO
WARNING
13. Turn on electrical power and verify proper unit operation.
Make sure furnace operates at the proper manifold pres-
sure at both high and low stage outputs.
Manifold Gas Pressure
Gas Rate
High Stage 9.7 to 10.3" w.c. 10.0" w.c.
Propane Gas
Low Stage
S-308 CHECKING HOT SURFACE IGNITOR
Goodman® and Amana® Distinctions
furnaces use a 120V carbide mini igniter for ignition. The
normal operating temperature is approximately 2550°F -
2876°F.
Amana brand 80% and 90% furnaces use a 80V Silicon
®
Nitride (SiNi) igniter for ignition. The nominal operating tem-
perature is approximately 2174°F. NOTE: The Silicon Ni-
tride Ignitor is not interchangeable with carbide ignition con-
trols.
WARNING
D ALL
ISCONNECT POWER BEFORE SERVICING.
1. Remove burner compartment door to gain access to the
ignitor.
2. Ignitor cool - approximately 70 - 77°F.
3. Disconnect the ignitor from the Ignition Control.
4. Using an ohmmeter measure the resistance of the igni-
tor:
Goodman® and Amana® Distinctions
and 90% furnaces: Carbide Mini Igniter should read be-
tween 30 to 300 ohms.
Amana® Brand 80% and 90% furnaces:
-
Nitride Igniter should read between 10.9 to 19.7 ohms.
5. Reconnect ignitor.
WARNING
L
INE VOLTAGE NOW PRESENT
6. Place unit in heating cycle, measure current draw of ig-
nitor during preheat cycle.
Goodman® and Amana® Distinctions
and 90% furnaces:
Should read approximately 1 amp maximum. The steady
state current at 120V is a nominal of .7 plus or minus .3
amps.
Range Nominal
5.7 to 6.3" w.c. 6.0" w.c.
Brand 80% and 90%
™
Brand - 80%
™
Brand - 80%
™