Table 5-1. Troubleshooting - Continued
6. Low oil pressure switch open,
inadequate fuel supply pressure
(closes at 45 psi at thermostat
j. Oil pressure switch bellows rup-
j. Oil emitting from pressure switch
bellow, assembly, replace pressure
outlet) - Continued
k. Fuel pump worn.
k. Remove pump, disassemble and
bearing, etc. for wear or breakage.
Replace defective parts or pump as
7. Excess pressure switch open (at 350
psi outlet pressure).
a. One discharge valve closed when on
two gun operation.
a. Observe valve positions, assure
both discharge valves are open.
b. Both discharge valves closed or
b. Observe valve positions, assure
both discharge valves fully open.
temperature rise in coil.
c. Observe temperature and outlet
pressure gages. Refer to operating
instructions for correct temperature
setting for desired operational mode.
d. Check valve in switch stuck in
closed position locking high pressure
in bellows assembly.
d. Remove sensing connection from
switch. Remove switch and inspect
check valve in bellows inlet assembly
for freedom of movement or foreign
material. Start pump and flush the
sensing connections. Clean check
valve, assuring it moves freely.
Replace switch as necessary.
e. Improper nozzle size on gun or guns
for operation mode.
e. Inspect nozzles in use, Refer to
operating instructions for nozzle size
used on desired operational mode.
f. Excessive scale buildup in nozzles,
restriction in guns or hoses.
f. Remove, inspect and descale nozzles
and guns. Pump water thru hose and
observe if flow is free. Blow air thru
hose or replace hose as necessary.
8. Flame failure "Red Indicator Light
On". (Flame signal voltage below 2V
a. Dirty scanner ultraviolet bulb.
a. Remove scanner, inspect bulb and
clean with a soft cloth with non-
b. Burner nozzle loose or off adapter.
b. Remove burner and inspect nozzles.
c. Burner nozzle connected to wrong
fuel valve (low fire and high fire
c. Remove burner and inspect nozzles,
correcting nozzles and fuel tubing as
necessary. Assure fuel tubing from
fuel valve is connected to proper
burner. 10 GPH nozzle should be on
low fire burner (farthest away from
scanner sight tube). 5 GPH nozzle
should be on high fire burner (closest
to sight tube).
d. Electrodes out of alignment.
d. Remove burner and check that
electrodes are adjusted to 1/16 to
proper dimensions or replace as
e. Electrodes out of alignment.
e. See malfunction 2, step m.
f. Electrodes cracked.
f. See malfunction 2, step n.
g. Burner nozzles dirty, plugged or
g. Remove burner and inspect nozzles.
Clean, repair or replace as necessary.
h. Defective scanners.
h. Scanner does not detect flame (zero
voltage at flame safeguard test
jacks). Replace scanner.
i. Oil or paint in scanner sight tube.
i. Remove burner and inspect sight
tube, clean off all oil and paint with