Table 5-1. Troubleshooting - Continued
3. Air pressure switch contacts open.
Inadequate air. (Switch closes at
0.15 WC) - Continued
d. Switch setting in-
correct - Continued
too high. Decrease set point by
terclockwise until burner ignites.
Test trip out point as indicated in
this corrective action.
e. Switch diaphragm ruptured.
e. Air will emit from open vent side of
switch. Replace switch.
f. Fan rotation incorrect.
f. Observe motor rotation. Should be
clockwise when viewed from front
(pulley end) of motor. Correct
rotation by reversing any two of the
three 3-phase power leads.
g. Fan belt loose.
g. Inspect belt for tightness. If it can
be twisted more than 2/3 of a turn,
tighten belt by adjusting oil pump in
slots in mounting base.
h. Improper air gate adjustment.
h. Inspect air gate. Open air gate until
sufficient air for combustion is
available. Observe exhaust; black
smoke, insufficient air; white smoke,
too much air.
i. Blower cage loose on shaft.
i. Remove air gate and blower intake
screen. Inspect, align and tighten
cage with setscrews in cage.
j. Blower drive pulley loose on shaft.
j. Inspect pulley. Remove belt and
tighten pulley with setscrew in
4. Inadequate water supply, low water
pressure switch open (needs 15 psig
to close) (refer to malfunction 1).
a. Water supply tank empty or par-
a. Observe water level in tank. Check
adjustment of float valve and for
adequate pressure and volume of
water at supply source.
b. Pump on-off suction valve closed or
b. Inspect position of valve handle and
that valve is in full open position.
c. Suction valves, lift and water tank,
open at same time.
c. Inspect position of valve handles.
Leave valve to the desired suction
source open, close other valve.
d. Water tank pump suction nipple off
e. Pump suction strainer is plugged.
e. Remove and inspect strainer, clean
f. Air leaks in pump suction piping.
f. Inspect piping for loose fittings,
hoses, hose clamps, etc. Inspect
suction valve bonnets for tightness.
g. Soap solution metering valve closed
(lift suction connection only).
g. Inspect valve position. Open valve.
h. Soap solution tank dry (air being
drawn into pump cylinder).
h. Observe tank solution level. Fill
soap solution tank.
i. Ruptured bellows on pressure
i. Water leakage around switch bellows
assembly. Replace pressure switch.
j. Sensing connection for pressure
j. Remove capillary connection and
fitting at sensing connection on pipe
cross of coil inlet assembly and
inspect for foreign material. Start
water pump and flush out connection
k. Switch setting incorrect.
h. Observe set point indicator on scale.
Cut-in setting should be 20 psi,
cutout setting 5 psi.
l. Air dome drain valve open.
i. Observe valve position. Water will
emit from drain. Close valve.