Carrier 58MTB - Manual (Page 6)

6
Table 3 – Speed Selection
COLOR SPEED
FACTORY
ATTACHED TO
White Common Com
Black High Cool
Yellow Medium High Spare
Orange
{
Medium High---Gas Heat
Blue Medium Low
Spare/High---Gas
Heat
Red Low* Low---Gas Heat
*Continuous blower speed.
{
Available on 5---speed blowers only.
ELECTRICAL SHOCK HAZARD
Failure to follow this warning could result in personal injury
or death.
Blower access door switch opens 115--v power to furnace
control. No component operation can occur. Caution must be
taken when manually closing this switch for service purposes.
!
WARNING
14. Turn on electrical supply. Manually close blower access
door switch. Use a piece of tape to hold switch closed.
Check for proper rotation and speed changes by performing
a component self--test as shown at the bottom of Service la-
bel. (See Fig. 20.)
15. If furnace is operating properly, remove tape to release
blower access door switch, replace blower access door, and
replace main furnace door.
Step 3 — Cleaning Burners
The following items should be performed by a qualified service
technician. If the burners develop an accumulation of light dirt or
dust, they may be cleaned by using the following procedure:
1. Turn off gas and electrical supplies to furnace.
2. Remove main furnace door.
3. Remove burner box cover.
4. Using backup wrench, disconnect gas supply pipe from fur-
nace gas control valve.
UNIT DAMAGE HAZARD
Failure to follow this caution may result in damage to furnace.
Label all wires prior to disconnection when servicing controls.
Wiring errors can cause improper and dangerous operation.
CAUTION
!
5. Remove wires from gas valve. Note location for reassembly.
6. Remove burner box pressure tube from gas valve regulator
fitting.
7. Unplug igniter from harness.
8. Remove igniter leads from slot in manifold grommet.
9. Remove screws that secure manifold to burner box. (See
Fig. 6.)
NOTE: Do not remove burner box from cell panel.
10. Remove manifold, orifices, and gas valve as 1 assembly.
11. Remove screws attaching burner assembly in burner box.
NOTE: Use care when removing and reinstalling burners not to
strike the hot surface igniter.
12. Remove burner assembly from burner box. NOTE: All
burners are attached to burner bracket and can be removed
as 1 assembly.
13. Clean burners with soft brush and vacuum.
14. Reinstall manifold, orifice, and gas valve assembly in burn-
er box. Ensure manifold seal grommet is installed properly
and burners fit over orifices.
15. Reinsert the igniter wires in the slot in the manifold grom-
met, dressing the wires to ensure there is no tension on the
igniter itself. (See Fig. 7.)
MANIFOLD
MOUNTING
SCREWS
MANIFOLD
GAS VALVE
REGULATOR
FITTING
GAS
CONTROL
VALVE
CELL
PANEL
GASKET
A02312
Fig. 6 -- Burner Box Assembly
IGNIT ER WIRES MUST
BE PLACED IN THIS SLOT
A05074
Fig. 7 -- Igniter Wire Placement
ELECTRICAL SHOCK HAZARD
Failure to follow this warning could result in electrical shock,
personal injury, or death.
Igniter wires must be securely placed in slot in manifold
grommet or else they could become pinched or severed and
electrically shorted.
!
WARNING
58MTB