Reznor RPB Unit Installation Manual - Manual (Page 37)

Form I-RPB, P/N 131782 R12, Page 37
10.2.2 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.
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 remove the
supply tubing, the drip shield and the lighter tube.
Propane - 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. Remove the main burner orifices.
5. Remove screws and lift out pilot burner.
Follow the instructions in Paragraph 10.2.3 to clean. To re-assemble and replace,
reverse the above procedures being careful not to create any unsafe conditions.
10.2.3 Cleaning Pilot
and 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 pres-
sure. 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.
Clean main burners and burner orifices using 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 in the
burner ports. Do not use anything that might change the port size.
Clean the burner rack carryover systems with air pressure.
10.2.4 Clean 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 38. (High CFM fur-
naces have only the top baffle support which does not need to be removed for clean-
ing.) To remove the baffles, remove the screws marked "A" in FIGURE 38, and slide
each baffle forward. Use a brush and/or an air hose to remove accumulated dust and
grease deposits from the heat exchanger 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 10.2.2.) 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. Furnaces designed to provide high efficiency
heating have "V" shaped baffles in the top of each heat exchanger tube. Follow the
instructions below to remove the "V" baffles when cleaning the inner surfaces of the
heat exchanger.
CAUTION: When
cleaning, wearing
eye protection is
recommended.