Burnham 20_PV_I - Manual (Page 20)

20
VIII. Service
A. General. Inspection and service should be conducted
annually. Turn off electrical power and gas supply
while conducting service or maintenance. Follow
instructions TO TURN OFF GAS TO APPLIANCE.
See Figure 17.
CAUTION
Label all wires prior to disconnection when
servicing controls. Wiring errors can cause
improper and dangerous operation. Verify proper
operation after servicing.
B. Inspect Housekeeping. Boiler area must be clear and
free from combustible materials, gasoline and other
flammable vapors and liquids. Remove obstructions to
the flow of combustion and ventilation air.
C. Service Low water cutoff (if so equipped). Follow
instructions provided with low water cutoff
D. Inspect Vent System for obstructions in vent pipe,
soot accumulation, deterioration of pipe or joints, and
proper support:
1. Remove vent connector and vent pipe. See Figure
19.
2. Remove all obstructions. Check and clean vent
terminal screens.
3. Remove soot accumulations with wire brush and
vacuum.
4. Replace deteriorated parts.
5. Repair deteriorated joints. See Section V: Venting,
Paragraph D.6.
E. Inspect Boiler Flue Passages for blockage or soot
accumulation. See Figure 19.
1. Disconnect vent connector from blower discharge
flange.
2. Remove sheet metal screws securing Jacket Top
Panel. Lift panel and rotate about relief valve
piping until top of boiler is exposed. If piping or
wall prevent full rotation of top panel for access to
canopy, cut slot into relief valve opening and
remove top panel.
3. Disconnect blower connection from wiring harness
in vestibule.
4. Remove bolts securing canopy to boiler sections.
Cut silastic sealant around base of canopy, pry
canopy from boiler sections and remove canopy/
blower assembly from boiler.
5. Using flashlight, examine all flue passageways.
a. If passageways are free of soot and obstruction,
replace canopy, secure and seal using kit
available from Burnham Distributors, Part No.
6111716.
b. If passageways need cleaning, remove burners
as described in Paragraph F below. Using long
handle wire or bristle flue brush and vacuum,
brush flueways thoroughly from top of boiler as
illustrated in Figure 19. Replace canopy and seal
using kit available from Burnham Distributors,
Part No. 6111716.
WARNING
Canopy must be resealed with RTV-732 Silicone
Rubber Sealant (500 F Intermittent Duty).
6. Reinstall jacket top panel, vent pipe and vent
connector in reverse manner. Reconnect electrical
connector to blower.
F. Clean Main Burners and Firebox.
1. To remove burners for cleaning, changing orifice
plugs, or repairs:
a. Remove jacket Front Panel.
b. Disconnect pilot tubing at gas valve.
c. Disconnect igniter/sensor cable and ground wire
at Ignition Module.
d. Disconnect Flame Rollout Switch wires.
e. Remove Burner Access Panel.
f. Mark Pilot Main Burner location on Manifold.
g. Hold burner on throat. Lift slightly to clear
orifice. Pull burner from combustion chamber.
See Figure 11. Pilot Main Burner can only be
removed by lifting at 45° angle after adjacent
burner to right is removed.
2. Brush top of burners with a soft bristle brush. See
Figure 19. Vacuum burners.
3. Check orifices. Drilled passageways must be free of
lint or dirt.
4. Vacuum tip of Pilot Burner.
5. Clean firebox by vacuuming. Exercise care not to
disturb insulation inside base.
6. Install burners by reversing procedure used to
remove burners. Burner with pilot assembly must
be in same location as original installation. See
Table 7. Burners must be properly located on