Carrier 59SU5A Manual page 54

59SU5A: Installation, Start-up, Operating and Service Maintenance Instructions
IGNITOR
POSITION
Fig. 66 – Igniter Position - Back View
1. Disconnect power at external disconnect, fuse or circuit breaker.
2. Turn off gas at external shut-off or gas meter.
3. Remove control door and set aside.
4. Turn electric switch on gas valve to OFF.
5. Disconnect Flame Sensor wire from Flame Sensor.
6. Remove the flame sensor burner assembly.
a. Using a 1/4-in. driver, remove the screw securing the flame
sensor to the burner assembly (see
factory-provided 1/4-in. screws.
b. Carefully withdraw the flame sensor from the burner assembly
without striking the sensor on surrounding parts.
c. Inspect flame sensor for signs of damage or failure.
d. Clean the flame sensor with fine steel wool (0000 grade). Do not
use sand paper or emery cloth.
e. If replacement is required, remove the screw that secures the
flame sensor on the bracket and remove the flame sensor.
7. To replace flame sensor and bracket assembly, reverse items 6a
through 6d.
8. Reconnect flame sensor wire to the wire harness, dressing the
sensor wires to ensure there is no tension on the flame sensor itself
(see Fig. 66).
WARNING
!
FIRE OR EXPLOSION HAZARD
Failure to follow this warning could result in personal injury, death,
and/or property damage.
Never purge a gas line into a combustion chamber. Never test for gas
leaks with an open flame. Use a commercially available soap solution
made specifically for the detection of leaks to check all connections. A
fire or explosion may result causing property damage, personal injury
or loss of life.
9. Turn gas on at electric switch on gas valve and at external shut-off
or meter
10. Turn power on at external disconnect, fuse or circuit breaker.
11. Run the furnace through two complete heating cycles to check for
proper operation
12. Install control door when complete.
Servicing Hot Surface Igniter
WARNING
!
FIRE OR EXPLOSION HAZARD
Failure to follow this warning could result in personal injury, death,
and/or property damage.
When servicing the flame sensor, only use the factory-provided 1/4-in.
length screws. Use of alternate screws will damage unit components.
The igniter does NOT require annual inspection. Check igniter
resistance before removal (see
Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.
FLAME
SENSOR
Fig. 66). Retain
Fig. 66).
1. Turn off gas and electrical supplies to furnace.
2. Remove control door.
3. Disconnect igniter wire connection.
4. Check igniter resistance. Igniter resistance is affected by
temperature. Only check resistance when the igniter is at room
temperature.
a. Using an ohm meter, check resistance across both igniter leads in
connector.
b. Cold reading should be between 40 ohms and 70 ohms.
A190266
5. Remove igniter assembly.
a. Using a 1/4-in. driver, remove the two screws securing the igniter
mounting bracket to the burner assembly (see
1/4-in. length screws.
b. Carefully withdraw the igniter and bracket assembly through the
burner assembly without striking the igniter on surrounding
parts.
c. Inspect igniter for signs of damage or failure.
d. Inspect the igniter gasket. If damaged or missing, replace gasket
before reinstalling.
6. To replace igniter and bracket assembly, reverse items 5a through
5d.
7. Reconnect igniter harness to the igniter, dressing the igniter wires to
ensure there is no tension on the igniter itself (see
8. Turn on gas and electrical supplies to furnace.
9. Verify igniter operation by initiating control board self-test feature.
Run the furnace through two complete heating cycles to check for
proper operation.
10. Replace control door.
Flushing Collector Box and Drainage System
ELECTRICAL SHOCK AND FIRE HAZARD
Failure to follow this warning could result in personal injury, death,
and/or property damage.
Turn off the gas and electrical supplies to the furnace and install lockout
tag before performing any maintenance or service. Follow the operating
instructions on the label attached to the furnace.
1. Turn off gas and electrical supplies to furnace.
2. Remove control door.
3. Disconnect pressure transducer tube from pressure transducer port.
NOTE: Ensure the pressure transducer tube disconnected from the
pressure transducer is higher than the collector box opening or water will
flow out of tube.
4. Remove the collector box plug from the top port on the upper
corner of the collector box (see
5. Attach a funnel with a flexible tube to port on the collector box.
6. Flush inside of collector box with water until discharge water from
condensate trap is clean and runs freely.
7. Repeat steps 4 through 6 with middle plug on upper corner of
collector box.
8. Remove the pressure transducer
NOTE: Do NOT blow into tube with tube connected to the pressure
transducer.
9. Clean pressure transducer port on collect box with a small wire.
Shake any water out of pressure transducer tube.
10. Reconnect tube to pressure transducer and pressure transducer port.
11. Remove the relief tube from the port on the collector box and the
trap.
54
Fig.
WARNING
!
Fig. 59).
tube from the collector box.
66). Retain
Fig. 66).