Carrier 59MN7B Installation, Start-Up, Operating And Service And Maintenance Instructions page 85

4. Align the orifices in the manifold assembly with the sup-
port rings on the end of the burner.
5. Insert the orifices in the support rings of the burners.
NOTE: If manifold does not fit flush against the burner, do not
force the manifold on the burner assembly. The burners are not
fully seated forward in the burner assembly. Remove the manifold
and check burner positioning in the burner assembly assembly
before re-installing the manifold.
6. Attach the green/yellow wire and ground terminal to one of
the manifold mounting screws.
7. Install the remaining manifold mounting screws.
8. Check the igniter alignment. See Fig. 68, 69 and 67.
9. Attach the wires to the roll-out switches.
10. Align the burner assembly with the openings in the prima-
ry cell inlet panel and attach the burner assembly to the cell
panel.
11. Connect the wire for the flame sensor.
12. Connect the wire for the Hot Surface Igniter.
NOTE: Use propane-resistant pipe dope to prevent leaks. Do not
use Teflon tape.
13. Install the gas pipe to the gas valve.
1-1/4-in.
(31.8)
2-1/2-in.
(64.4)
Fig. 68 - - Igniter Position - - Top View
Fig. 69 - - Igniter Position - - Side View
A11405
2 in.
50 mm
3/8 in.
9.6 mm
3/16 in.
4.6 mm
+ 1/32
1/10 in.
1/16 in.
+0.8
2.5 mm
1.5 mm
L12F041
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.
14. Check for gas leaks with a commercially available soap so-
lution made specifically for the detection of leaks.
15. Turn gas on at electric switch on gas valve and at external
shut-off or meter
16. Turn power on at external disconnect, fuse or circuit break-
er.
17. Run the furnace through two complete heating cycles to
check for proper operation
18. Install control door when complete.
Servicing Hot Surface Igniter
The igniter does NOT require annual inspection. Check igniter
resistance before removal. Refer to Fig. 68, 69 and 67.
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.
Resistance reading will increase as igniter temperature in-
creases.
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 Fig.
67.
b. Carefully withdraw the igniter and bracket assembly
through the front of the burner assembly without striking
the igniter on surrounding parts.
c. Inspect igniter for signs of damage or failure.
d. If replacement is required, remove the screw that secures
the igniter on igniter bracket and remove the igniter.
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
Fig. 67.
8. Turn on gas and electrical supplies to furnace.
9. Verify igniter operation by initiating control board self- -test
feature or by cycling thermostat.
10. Replace control door.
85