68
SSCBL-RPBL-IOM (10-22) 149159-C
MAINTENANCE—CONTINUED
Service Checklist
The following section is designed to aid a qualified service person in maintaining and servicing this equipment . At a
minimum, perform the following annually:
Inspect filters and clean or replace as necessary .
Inspect blower and belt—check belt for tension, wear, and alignment (adjust or replace as needed) and clean
dirt from blower and motor .
Check gas valve to ensure that gas flow is being shut off completely .
Clean heat exchanger both internally and externally .
Check pilot burner and main burners for scale, dust, or lint accumulation and clean as necessary .
Clean all dirt and grease from primary and secondary combustion air openings .
Check flue products outlet and clean as necessary .
Check vent cap in optional extended vent system and replace any parts that do not appear sound .
Check vent/combustion air system, inspect all joints, and replace any parts that do not appear sound .
Check main burner ports, carryover assemblies, and orifices for cleanliness .
Check wiring for any damaged wire—replace damaged wiring (refer to
requirements)
Maintenance Procedures
Combination Gas Valve Maintenance
⚠ WARNING ⚠
The combination gas valve is the prime safety shutoff. To ensure positive closure, all gas supply
lines must be free of dirt or scale before connecting them to the unit.
Remove external dirt accumulation and check wiring connections . The combination gas valve must be checked
annually as follows to ensure that the valve is completely shutting off gas flow .
1 . Locate 1/8-inch FPT INLET pressure tap on combination gas valve (see
) .
NOTE: A manometer (fluid-filled gauge) with an inches water column scale is recommended.
2 . With field-installed manual valve closed to prevent flow to gas valve, connect manometer to 1/8-inch FPT INLET
) .
Figure 49. Combination Gas Valve Test Connections
SINGLE-STAGE VALVE
1/8-INCH INLET
PRESSURE TAP
1/8-INCH OUTLET
PRESSURE TAP
1/8-INCH OUTLET
PRESSURE TAP
TWO-STAGE VALVE
1/8-INCH INLET
PRESSURE TAP
HIGH FIRE
REGULATOR
ADJUSTING
SCREW
LOW FIRE
REGULATOR
ADJUSTING
SCREW
REGULATOR
ADJUSTING
SCREW
