T.O. 35 C2-3-442-2
j . Inspect heat exchanger and burner
2. Check continuity of micro-switch
assembly for warpage and burned area.
(16) as follows:
k. Inspect sintered filter for blockage.
(a) Depress the micro-switch
button. This will be the ignition or start
1. Using a suitable dial indicator, check
end play on shaft of blower motor assembly.
indicated between the two NO terminals and
Grasp short shaft end and rotate in either
also between each of the NO terminals and
direction, at the same time moving in and
the common terminal. There should be an
out. The end play should not exceed 0.010
open circuit between the two NC terminals
to 0.025 inch.
and also between the common terminal and
the two NC terminals.
m. Inspect adapter for damaged or
scored face, warped condition, and dam -
(b) Release the micro-switch
button. This will be the run position of the
aged seal face. Inspect for motor shaft
cated between the two NC terminals and the
n. Inspect seal cage for scored or dam-
common terminal. There should be an open
aged seal face.
circuit between the NO ignition or start ter-
minals and between the NO terminals and
o. Inspect rotor and blades for damage
the common terminal.
h. Inspect igniter as follows:
p. Inspect cam ring for damaged or
1. Inspect for broken coil or short.
scored bore. Inspect for warped condition.
Both faces must be parallel within 0.001 inch
2. Check igniter for proper resis-
T. I. R.
damaged or scored face.
11-14. R E P A I R .
To prevent burns, do not touch
igniter during test, and allow enough
and seal face of seal cage (71) can be
time for it to return to ambient
dressed to remove minor nicks, scratches
temperature before removing test
or scoring. Remove only material neces-
sary to clean up seal face. Seal face must
be parallel with rotor side of adapter within
3. Connect 24 VDC power source and
0.001 inch per inch. Replace either part if
an ammeter to igniter terminal. Ground
imperfections cannot be dressed cut.
igniter. Apply 24 VDC to igniter. The
igniter should draw 10.5 amperes and heat
b. Straighten distorted parts using
to a bright red color in a few seconds.
i. Inspect fan for loose or damaged
c. Remove burrs or nicks using a stone