AERCO KC1000 Low NOx Boiler July 2011 - Manual (Page 57)

MAINTENANCE
7-3
7. Loosen the 1/4” NPT union on the low NOx
staged ignition assembly (Figure 7.3).
8. Disconnect the staged ignition assembly
1/8” elbow from the 3” long NPT nipple at
the bottom of the burner shell.
LOW NOx
BURNER
SHELL
STAGED IGNITION
ASSEMBLY
1/8" STREET
ELBOW
1/8" NPT
NIPPLE
3" LONG
1 /4-20
HEX NUTS
(4)
GAS INLET
PIPE
HOSE
CLAMP
AIR/FUEL
VALVE
5/16-18
HEX NUTS (6)
3/8-16 HEX
NUTS &
BOLTS (2)
1/4" NPT UNION
1/4" O.D.
TUBE
Figure 7.3
Burner Disassembly Diagram
9. Remove the 3” long NPT nipple and 1/4”
O.D. tube (Figure 7.3) from the burner shell.
10. Using a 7/16” socket or open end wrench,
remove the four 1/4-20 nuts on the gas inlet
pipe flange at the burner.
11. Using two 9/16” wrenches, remove the two
3/8-16 hex nuts and bolts on the gas inlet
pipe flange at the air/fuel valve (Figure 7.3).
Remove the gas inlet pipe.
12. Loosen the hose clamp on the air/fuel valve
outlet (Figure 7.3).
13. Using a 1/2” socket wrench, remove the six
5/16-18 hex nuts supporting the burner
(Figure 7.3).
14. Lower the burner while sliding the air hose
off the air/fuel valve. Remove the burner
through the rear of the unit. Due to space
limitations, it will be necessary to separate
the burner head and shell during the
removal process.
15. Disconnect the exhaust temperature sensor
by unscrewing it from the exhaust manifold
(Figure 7.4).
EXHAUST
TEMP.
SENSOR
Figure 7.4
Exhaust Sensor Connector Location
16. Disconnect the air/fuel valve 12-pin con-
nector from the KC wiring harness.
17. Disconnect wires #24 and #17 from the
blower proof switch (Figure 7.5).
AIR/FUEL VALVE
BLOWER PROOF
SWITCH
TO FRAME
HARNESS
Figure 7.5
Blower Proof Switch Wire Locations
18. Loosen the hose clamp on the air/fuel valve
inlet and slide the clamp back towards the
blower (Figure 7.6).
HOSE CLAMP
Figure 7.6
Air/Fuel Valve Inlet Hose Clamp