50
Integrated
Gas Unit
Controller
(IGC)
Induced Draft
Motor
Rollout
Switch
Mounting
Screw
Burner
Rack
Inducer
Blower
Housing
Flue
Collector
Box
Interface Fan
Board (IFB)
Auto Transformer
fuses used on 460
volt units only.
(Hidden)
Fan Partition
Mounting
Bracket
A09193
Fig. 18 -- Blower Housing and Flue Collector Box
COMPRESSOR
ACCESS PANEL
BLOWER
ACCESS
PANEL
CONTROL
ACCESS
PANEL
A09207
Fig. 19 -- Unit Access Panels
Induced Draft (combustion air) Blower Assembly
The induced--draft blower assembly consists of the inducer motor,
the blower housing, and the induced--draft blower wheel.
Clean periodically to assure proper airflow and heating efficiency.
Inspect blower wheel every fall and periodically during the heating
season. For the first heating season, inspect blower wheel
bimonthly to determine proper cleaning frequency.
To inspect blower wheel, remove draft hood assembly. Shine a
flashlight into opening to inspect wheel. If cleaning is required,
remove induced--draft blower assembly as follows:
1. Remove control access panel (See Fig. 19).
2. Remove the 5 screws that attach induced--draft blower as-
sembly to the flue collector box cover.
3. Slide the assembly out of the unit. (See Fig. 20). Clean the
blower wheel. If additional cleaning is required, continue
with Steps 4 and 5.
4. To remove blower wheel, remove 2 setscrews.
5. To remove inducer motor, remove screws that hold the
inducer motor to the blower housing.
6. To reinstall, reverse the procedure outlined above.
Flue Gas Passageways
To inspect the flue collector box and upper areas of the heat
exchanger:
1. Remove the induced draft blower assembly according to
directions in the Induced Draft Blower Assembly section.
2. Remove the 11 screws holding the flue collector box cover
(See Fig. 18) to the heat exchanger assembly. Inspect the
heat exchangers.
3. Clean all surfaces, as required, using a wire brush.
Limit Switch
Remove blower access panel (see Fig. 19). Limit switch is located
on the fan partition.
Burner Ignition
Unit is equipped with a direct spark ignition 100 percent lockout
system. Ignition module (IGC) is located in the control box (See
Fig. 18). Module contains a self--diagnostic LED. During
servicing, refer to label diagram or Table 5 in these instructions for
LED interpretation.
If lockout occurs, unit may be reset by either momentarily
interrupting power supply to unit or by turning selector switch to
OFF position at the thermostat.
Main Burners
At the beginning of each heating season, inspect for deterioration
or blockage due to corrosion or other causes. Observe the main
burner flames and adjust, if necessary.
Removal of Gas Train
To remove the gas train for servicing:
1. Shut off main gas valve.
2. Shut off power to unit and install lockout tag.
3. Remove control access panel (See Fig. 19).
4. Disconnect gas piping at unit gas valve.
5. Remove fan partition mounting bracket (2 screws located
on the left side of control compartment on the fan partition
panel). Slide bracket forward, bottom first to remove. (See
Fig. 18).
6. Remove wires connected to gas valve. Mark each wire.
7. Remove ignitor and sensor wires at the ignitor module.
8. Remove the mounting screw that attaches the burner rack to
the unit base (See Fig. 18).
9. Slide the burner rack out of the unit (See Fig. 18 and 21).
10. To reinstall, reverse the procedure outlined above.
11. Check all connections for leaks.
FIRE, EXPLOSION HAZARD
Failure to follow this warning could result in personal injury,
death or property damage.
Do not purge gas supply into the combustion chamber. Do not
use a match or other open flame to check for gas leaks. 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.
!
WARNING
Outdoor Coil, Indoor Coil, and Condensate Drain Pan
Inspect the outdoor coil, indoor coil, and condensate drain pan at
least once each year. The coils are easily cleaned when dry;
therefore, inspect and clean the coils either before or after each
cooling season. Remove all obstructions, including weeds and
shrubs, that interfere with the airflow through the condenser coil.
Straighten bent fins with a fin comb. If coated with dirt or lint,
clean the coils with a vacuum cleaner, using the soft brush
attachment. Be careful not to bend the fins. If coated with oil or
grease, clean the coils with a mild detergent--and--water solution.
Rinse coils with clear water, using a garden hose. Be careful not to
splash water on motors, insulation, wiring, or air filter(s). For best
results, spray outdoor coil fins from inside to outside the unit. On
units with an outer and inner condenser coil, be sure to clean
677C
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--
C
Summary of Contents for Legacy 677C**C Series
Page 3: ...3 A150538 Fig 2 24 30 Unit Dimensions 677C C...
Page 4: ...4 A150539 Fig 3 36 60 Unit Dimensions 677C C...
Page 44: ...44 A150506 Fig 15 208 230 1 60 Connection Wiring Diagram 677C C...
Page 45: ...45 A150516 Fig 15 Cont 208 230 1 60 Ladder Wiring Diagram 677C C...
Page 46: ...46 A150507 Fig 16 208 230 3 60 Connection Wiring Diagram 677C C...
Page 47: ...47 A150517 Fig 16 Cont 208 230 3 60 Ladder Wiring Diagram 677C C...