7500-S
ERIES
I
NSTALLATION
, O
PERATION
AND
S
ERVICE
M
ANUAL
134 of 143
Oil Operation (continued)
PROBLEM
POSSIBLE CAUSE
SOLUTION
White Smoke Formation
on Oil Firing
Oil/Air ratios incorrect d
u
e to excess air, or oil flo
w
is too lo
w
.
Readj
u
st for proper f
u
el inp
u
t, CO2
and smoke reading.
Gray or Black Smoke
Formation on Oil Firing
Defecti
v
e or dirty oil nozzle.
Replace or clean nozzle.
Incorrect oil/air ratios.
Readj
u
st
bu
rner to correct CO2 and
smoke le
v
els.
Oil press
u
re too lo
w
res
u
lting in poor atomization.
Readj
u
st.
Impingement of ra
w
oil spray on the
b
last t
ub
e
choke ring or oil nozzle air diff
u
ser.
Make certain that the diff
u
ser is
seated firmly against the oil nozzle
adapter sho
u
lder. Position the oil
g
u
n assem
b
ly fore or aft in the
b
last
t
ub
e to assist in elimination of oil
spray on the
b
last t
ub
e choke ring.
Oil High Fire Inp
u
t Rate
Cannot Be Achie
v
ed
Nozzle defecti
v
e or mesh filter dirty.
Replace or clean mesh.
Oil s
u
pply press
u
re to nozzle too lo
w
. Readj
u
st.
Oil p
u
mp defecti
v
e.
Replace.
On Lo
w
/High/Off and Lo
w
/High/Lo
w
systems - Nor-
mally closed oil solenoid
v
al
v
e in nozzle ret
u
rn line
not closing (or leaking).
Check
v
al
v
e operation and replace if
necessary.
On t
w
o-step p
u
mp - Normally open p
u
mp mo
u
nted
oil solenoid
v
al
v
e defecti
v
e (not closing).
Replace
v
al
v
e or p
u
mp.
Oil p
u
mp co
u
pling loose (slipping) or defecti
v
e. Replace.
Linkage mechanically
b
inding. Readj
u
st.
On mod
u
lating
bu
rner, oil nozzle ret
u
rn line meter-
ing
v
al
v
e set incorrectly.
Readj
u
st to attain req
u
ired nozzle
b
ypass press
u
re.
Oil s
u
ction line is partially
b
locked. Clean.
Blocked or dirty s
u
ction line oil filter.
Replace or clean.
Man
u
al
v
al
v
es in s
u
ction line not f
u
lly open.
Check and correct.
S
u
ction line check
v
al
v
e or foot
v
al
v
e operating
incorrectly.
Check and correct.
Vent system on oil tank
b
locked creating
v
ac
uu
m on
tank,
w
ith high
v
ac
uu
m and lo
w
ered oil flo
w
to
bu
rner.
Check and correct.