TM 9-4940-342-14&P
(4) Connect fuel supply, fuel to burner and oil
pressure switch sensing copper tubing connections to
valve assembly.
(5) Install front fire panel and electrical control
box cover.
5-35. Low Fire Fuel Solenoid Valve (Refer to Fig
C-13)
a. Removal. To remove the low fire fuel solenoid
valve proceed as follows:
(1) Accomplish procedures in paragraph 5-34a,
steps (1) and (2).
(2) Disconnect valve electrical leads no. 2 and
7 from lower half of electrical control box terminal
board.
(3) Accomplish procedures in paragraph 5-34a,
steps (4) and (5).
b. Installation. To install low fire fuel solenoid
valve proceed as follows:
(1) Accomplish procedures in paragraph 5-34b,
steps (1) and (2).
(2) Connect valve electrical leads to control
terminal board terminals 2 and 7.
(3) Connect fuel supply from thermostat, fuel
supply to high fire valve and fuel to burner tubing
connection to valve assembly.
(4) Install front fire panel and electrical control
box cover.
5-36. Control Power Transformer (Refer to Fig
C-13)
a. Removal.
To
remove
control
power
transformer proceed as follows:
(1) Remove electrical control box cover.
(2) Remove conductors from primary and
secondary terminals of transformer.
(3) Loosen and remove four mounting screws,
nuts and lockwashers securing transformer to box.
(4) Remove transformer from box.
b. Installation. To install the control power
transformer proceed as follows:
(1) Align transformer base mounting holes
with control box mounting holes.
(2) Secure transformer to box with four
mounting screws, nuts and lockwashers.
(3) Connect electrical conductors to trans-
former primary and secondary.
(4) Replace electrical control box cover.
5-37. Ignition Transformer (Refer to Fig C-13)
a. Removal. To remove the ignition transformer
proceed as follows:
(1) Remove front fire panel and electrical
control box cover.
(2) Disconnect ignition transformer electrical
leads no. 2 and 4 from lower half of electrical
control box terminal board.
(3) Disconnect
ignition
electrodes
from
transformer secondary prongs on back side of-box.
(4) Loosen and remove upper transformer
mounting screw, nut and lockwasher.
(5) Loosen lower transformer mounting screw.
(6) Slide transformer up and out from lower
mounting screw, remove from box.
b. Installation. To install the ignition transformer
accomplish procedures in paragraph 5-37a, steps (1)
through (6) in the reverse order.
5-38. Excess Pressure Switch (Refer to Fig C-13)
a. Removal. To remove excess pressure switch
proceed as follows:
(1) Remove front fire panel and electrical
control box cover.
(2) Remove switch cover.
(3) Disconnect electrical leads at switch
terminals.
(4) Disconnect switch sensing connection to
switch bellows assembly.
(5) Remove two switch mounting screws from
back side of box.
(6) Remove switch from box.
b. Installation. To install the excess pressure
switch proceed as follows:
(1) Align switch with mounting holes in box.
(2) Accomplish procedures in paragraph 5-38a,
steps (1) through (5) in the reverse order.
5-39. Water Pressure Switch (Refer to Fig C-13)
a. Removal. To remove the water pressure switch
proceed as follows:
(1) Remove front fire panel and electrical
control box cover.
(2) Remove switch cover.
(3) Disconnect electrical leads at switch
terminals.
(4) Disconnect switch sensing capillary at
connection to coil inlet assembly.
(5) Remove two switch mounting screws from
back side of box.
(6) Remove switch together with attached
capillary from box.
b. Installation. To install the water pressure
switch proceed as follows:
(1) Align switch with mounting holes in box.
(2) Secure switch with two mounting screws,
insert screws from back side of box.
(3) Route switch pressure sensing capillary
through hole provided in bottom panel of box and
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