Carrier 58MCB - Manual (Page 10)

10
16. Replace main furnace door.
Step 6 — Servicing Hot Surface Igniter
The igniter does NOT require annual inspection. Check igniter
resistance before removal.
1. Turn off gas and electrical supplies to furnace.
BURN HAZARD
Failure to follow this caution may result in personal injury.
Allow igniter to cool before removal. Normal operating
temperatures exceed 2000_F (1093_C).
CAUTION
!
2. Remove main furnace 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 ig-
niter leads in connector.
b. Cold reading should be between 40 ohms and 70 ohms.
5. Remove igniter assembly.
a. Remove burner box cover.
b. Remove igniter wires from slot in manifold grommet.
(See Fig. 7.)
c. Using a 1/4--in. driver, remove the single screw securing
the igniter bracket to the burner box bracket (See Fig.
13.) and carefully withdraw the igniter and bracket as-
sembly through the front of the burner box without
striking the igniter on surrounding parts. Note that the
igniter bracket has a handle that extends to the front of
the burner box to aid in handling. (See Fig. 13.)
d. Inspect igniter for signs of damage or failure.
UNIT DAMAGE HAZARD
Failure to follow this caution may result in premature
failure of the igniter.
The igniter is fragile. DO NOT allow it to hit burner box
parts while removing or replacing it.
CAUTION
!
e. If replacement is required, replace igniter on igniter
bracket and then install assembly into burner box to
avoid damage to the igniter.
6. To replace igniter and bracket assembly, reverse items 5a
through 5c.
7. Reconnect igniter wire connection and insert the igniter
wires in the slot in the manifold grommet, dressing the ig-
niter wires to ensure there is no tension on the igniter itself.
(See Fig.7.)
8. Reinstall burner box cover.
9. Turn on gas and electrical supplies to furnace.
10. Verify igniter operation by initiating control board self--test
feature or by cycling thermostat.
11. Replace main furnace door.
;; ;;
BURNER FLAME
BURNER
MANIFOLD
A89020
Fig. 11 -- Burner Flame
RTV
PAM
A93081
Fig. 12 -- Gasket on Collector Box
BRACKET
IGNITER
9/16˝
11/16˝
EXTENDED IGNITER
BRACKET HANDLE
IGNITER BRACKET
MOUNTING SCREW
A05075
Fig. 13 -- Igniter Bracket
58MC
B