Form I-XE/CRGB/RPB, Page 42
Top Baffle
Support
Screws B
Bottom
Baffle Support
Brackets
Air
Discharge
Dir
ection of
Airflow
Screw C
Right
Left
Screws A
Scr
ew C
Flue Diverter
(Sizes 225-400 only)
Tube Baffle
Collection Box End
Blockoff Plate
Screw
Collection
Box End
Screw
FIGURE 48 -
When cleaning
outer heat
exchanger
surface, remove
directional
air baffles.
Remove Screws
"A" and slide
baffles out.
Clean and
replace all
baffles.
NOTE: High
CFM furnaces
do not have
directional air
baffles.
38. Burner Rack Removal
Instructions
1.
Turn off the gas supply.
2.
Turn off the electric supply.
3.
Remove control access side panel.
4.
Disconnect the pilot tubing and flame sensor lead (spark pilot).
5.
Mark and disconnect electric valve leads.
6.
Uncouple the union in the gas supply.
7.
Remove sheetmetal screws in the top corners of the burner
rack assembly.
8.
Pull "drawer-type" burner rack out of the furnace.
To disassemble the burner rack:
1.
Remove Carryover System -
Natural Gas
- Remove the flash carryover system from the
"manifold end" of the burner rack.
NOTE:
Natural gas burner
racks manufactured prior to 3/95 have a lighter tube carryover
system. Break the lighter tube connection at the orifice and re-
move the supply tubing, the drip shield and the lighter tube.
Propane Gas
- Break the lighter tube connection at the regulator
and remove the lighter tube orifice supply tubing; remove the
retaining screws in the drip shield and the shield; remove the
retaining screws and slide out the lighter tube.
2.
Pull main burners horizontally away from injection opening
and lift out.
3.
Remove manifold bracket screws and remove manifold.
4.
Change main burner orifices, if necessary.
5.
Remove screws and lift out pilot burner.
Follow the instructions in Paragraph 39 to clean. To re-assemble and
replace, reverse the above procedures being careful not to create any
unsafe conditions.
CAUTION: When cleaning, wearing eye
protection is recommended.
39. Cleaning Pilot & Main Burners
In the event the pilot flame is short and/or yellow, check the pilot
orifice for blockage caused by lint or dust accumulation. Remove the
pilot orifice and clean with air pressure. DO NOT REAM THE
ORIFICE. Check and clean the aeration slot in the pilot burner.
Clean the metal sensing probe and the pilot hood with an emery
cloth and wipe off the ceramic insulator. Check the spark gap; spark
gap should be maintained to 7/64". After the pilot is cleaned, blow
any dirt away with compressed air. (See ignition requirements in
Paragraph 27.)
Clean the main burners with air pressure. Use an air nozzle to blow
out scale and dust accumulation from the burner ports. Alternately
blow through the burner ports and the venturi. Use a fine wire to
dislodge any stubborn particles. Do not use anything that might
change the port size.
Clean the burner rack carryover systems with air pressure.
40. Cleaning the Heat Exchanger
To clean the outer surfaces (circulating air side) of the heat exchanger,
gain access by removing the inspection panels in the ductwork or
remove the ductwork. Depending on whether or not the furnace is
designed for high CFM (Model prefix "H"), there may be directional
baffles between the heat exchanger tubes. The standard furnace has
baffles between the heat exchanger tubes as shown in
FIGURE 48
.
(High CFM furnaces have only the top baffle support which does
not need to be removed for cleaning.) To remove the baffles, remove
the screws marked "A" in
FIGURE 48,
and slide each baffle forward.
Use a brush and/or an air hose to remove accumulated dust and
grease deposits from the tubes and the baffles. Re-install the baffles
by sliding them into the rear slot and replacing the screw.
The inner surfaces (combustion air side) of the heat exchanger can be
reached for cleaning with the burner rack removed. (See Paragraph
38.) An air hose; an 18-24" long, 1/2" diameter furnace brush (or heavy wire
with steel wool securely attached); a flashlight; and a mirror are needed.
The required procedure depends on the date of manufacture and whether or
not the furnace is rated for high (80%) efficiency. Furnaces designed to
provide high efficiency heating have "V" shaped baffles in the top of each
heat exchanger tube. Follow these instructions to remove these baffles
when cleaning the inner surfaces of the heat exchanger.
NOTE:
High efficiency furnaces manufactured prior to 3/95 have a "C"
prefix in their model designation. All furnaces manufactured beginning 3/95
are designed for high efficiency and include these heat exchanger "V" baffles.
Instructions to Remove Heat Exchanger "V" Baffles:
Outdoor, Gravity Vent Model Series CRGB (See FIGURE 49)
1) Remove the ends of the flue gas collection box. On the control side of
the furnace, remove the block-off plate to gain access to the collection
box end.
2)
Sizes 75-175
- Remove one of the tube baffle retaining angles on each
inside wall of the collection box. Each angle has one screw.
Sizes 200-400
- Remove the flue diverter. Remove the screw at each
end and slide the flue diverter out of the furnace.
3) Pull the "V" baffles out of the heat exchanger.
Outdoor, Power Vent Model Series RPB
1) Remove the ends of the flue gas collection box. On the control side of
the furnace, remove the venter assembly and the flue outlet duct to
gain access to the collection box end.
2)
Sizes 125-300
- Remove one of the tube baffle retaining angles on
each inside wall of the collection box. Each angle has one screw.
Size 400
- Remove the inner baffle from the flue collection box. On
the control side, align the inner baffle with the slot in the collection
box edge. Pull the inner baffle until it clears the heat exchanger.
Remove the screw at each end and slide the flue diverter out of the
furnace.
3) Pull the "V" baffles out of the heat exchanger.
FIGURE 49 -
Remove
"V" Baffles to Clean Inner Surface of Heat Exchanger Tubes
