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SSCBL-RPBL-IOM (10-22) 149159-C
3 . With field-installed manual valve closed, turn up thermostat to fire unit and to allow unit to go through one trial
for ignition .
4 . Reset thermostat to shut OFF unit and observe manometer for 2 to 3 minutes for indication of gas pressure . No
pressure should be indicated on manometer . If manometer indicates gas pressure, field-installed manual gas
valve must be replaced or repaired before combination gas valve can be checked .
5 . If manometer does not indicate gas pressure, slowly open field-installed manual gas valve . After manometer
indicates that gas pressure has reached equilibrium, close manual shutoff valve .
NOTE: Refer to
section for operational pressure settings and instructions
for checking pressure settings.
6 . Observe gas pressure on manometer . There should be no loss of gas pressure . If manometer indicates loss of
gas pressure, replace combination gas valve before placing heater in operation .
Burner Rack Maintenance
Remove, disassemble, clean, reassemble, and re-install burner rack as follows:
1 . Remove burner rack:
a . Turn OFF gas and electric supply .
b . Remove control access side panel .
c . Disconnect any pilot lines and flame sensor leads .
d . Mark and disconnect electric valve leads .
e . Uncouple union in gas supply .
f . Remove sheet metal screws in top corners of burner rack assembly .
g . Pull drawer-type burner rack out of furnace .
2 . Disassemble burner rack:
NOTE: Natural gas burner racks manufactured
before
1997 may 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.
a . For natural gas burner rack, remove flash carryover system from manifold end of burner rack .
b . For propane gas burner rack:
(1) Break lighter tube connection at regulator and remove lighter tube orifice supply tubing .
(2) Remove retaining screws in drip shield and remove shield .
(3) Remove retaining screws and slide out lighter tube .
c . Pull main burners horizontally away from injection opening and lift out .
d . Remove manifold bracket screws and remove manifold .
e . Remove burner orifices .
f . Remove screws and lift out pilot burner .
3 . Clean burner rack in accordance with instructions in
section .
4 . Replace burner orifices (refer to
) as necessary .
5 . Re-assemble and re-install burner rack by reversing above steps, being careful not to create any unsafe conditions .
