(f) Unscrew and remove the electrodes
(8 and 12, fig. 4-26) with the gaskets from the holder.
a. Description.
Separate the gaskets from the electrodes.
(1) Burner sight hole cap assembly. The
(g) Unscrew and remove the nozzle
burner sight hole cap assembly is located on the left end
with the adapter from the fuel nozzle adapter nipple.
of the water heater. It is used to check the flame in the
(h) Loosen the two setscrews that
heater combustion chamber.
secure the adapter nipple to the holder, and remove the
(2) Electrode sight tube glass, gasket and
adapter nipple.
bushing. The electrode sight tube glass is mounted on
(i) Remove the sight tube nipple (2)
the burner nozzle and electrode holder. It is used to
from the holder.
check the electrode sparks.
(5) Burner fuel nozzle, adapter and nipple.
(3) Drain cock (combustion chamber). This
(a) Remove the burner nozzle and
drain cock is located on the left end of the water heater
electrode holder from the burner assembly (para b (4)
tank. It is used to drain the condensation from the
(a) thru (d)).
combustion chamber.
(b) Remove the adapter with nozzle
(4) Burner electrodes, holder and gaskets.
from the fuel nozzle adapter nipple.
The two burner electrodes are mounted in the holder on
(c) Remove the nozzle (1, fig. 4-28)
the burner head. They are terminals between which the
with screen (2) from the adapter (3).
electric current passes creating a spark to ignite the fuel
(d) Unscrew and remove the screen (2)
in the combustion chamber.
from the nozzle.
(5) Burner fuel nozzle, adapter and nipple.
(e) Remove the nipple from the holder.
The burner fuel nozzle, mounted on the inner side of the
(6) Burner head, gasket and air nose.
nozzle and electrode holder, sprays the fuel into the
(a) Remove the burner nozzle and
combustion chamber.
electrode holder (para b(4) and b(5)) above.
(6) Burner head, gasket and air nose. The
(b) Remove the four nuts (1, fig. 4-26)
burner head and air nose serve as a flame diffuser and
and lockwashers that secure the burner head to the
air shield.
water heater.
b. Removal
(c) Remove the burner head (1, fig. 4-
(1) Burner sight hole cap assembly. Unscrew
and remove the assembly (7, fig. 4-26) from the sight
(d) Remove the two screws that secure
tube on the water heater.
the air nose (3) to the burner head, and separate the air
(2) Electrode sight tube glass, gasket and
nose from the burner head.
bushing.
c. Inspection.
(a) Unscrew and remove the bushing
(1) Burner sight hole cap assembly. Inspect
with the glass (6, fig. 4-26) and the gasket from the
the cap assembly for broken or cracked glass and for
sight tube nipple (2). Separate the bushing, the glass,
stripped or damaged threads.
and the gasket.
(2) Electrode sight tube glass, gasket and
(b) Unscrew and remove the nipple (2)
bushing. Inspect for broken or cracked glass and
from the nozzle and the electrode holder.
leaking gasket.
Check the bushing for damaged
(3) Drain cock (combustion chamber).
threads.
Unscrew and remove the drain cock from the water
(3) Drain cock (combustion chamber).
heater.
Inspect the drain cock for proper seating in closed
(4) Burner electrodes, holder and gasket.
position, for damaged or stripped threads, for broken
handle, and for clogged openings.
(a) Unscrew and remove the cable
(4) Burner electrodes, holder and gaskets.
assemblies (9 and 11, fig. 4-26) from the electrodes (8
Inspect for broken, cracked, and distorted holder and
and 12).
nipples and for damaged threads.
Inspect the
(b) Unscrew and remove the fuel feed
electrodes for burned spots, and inspect the insulator for
line assembly (10) from the elbow.
cracks, breaks and lines (etchings). Check for broken
(c) Remove the three nuts (3) and
or distorted gaskets.
lockwashers that secure the holder (5) to the burner
(5) Burner fuel nozzle, adapter and nipple.
assembly (4).
Inspect for clogged, cracked, and excessively worn
(d) Remove the holder with the
nozzle. Inspect the nozzle for carbon deposits, the
electrodes from the burner assembly as shown in figure
nozzle screen for broken mesh and dirty or clogged
passages, and the adapter for damaged threads.
(e) Bend the electrode wires so they
(6) Burner head, gasket and air nose.
will not strike the nozzle when the electrodes are
Inspect for dirty, broken, cracked, and bent burner head
removed.
and air nose. Check for carbon deposits on the burner
head and the air nose.
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