Rapid 7500 136 Installation, operation & service manual - page 47
Manual is about: 7500-Series
Indirect, Gas/Oil-Fired,
Industrial Air Turnover Unit
of
156
SECTION 10: B
URNERS
35 of 143
FIGURE 20: "Type C" Burner with I
g
nition Electrode - Natural Gas or LPG
NOTE:
"Type C" Gas B
u
rner - The arc from the
electrode tip sho
u
ld j
u
mp from the tip to the
b
ody of
pilot ho
u
sing and sho
u
ld
b
e lined
u
p
w
ith the hole in
the
b
ackside of pilot ho
u
sing, so that the
b
lo
w
er air
passing thro
u
gh this hole
w
ill ca
u
se the arc to flag or
mo
v
e aro
u
nd. Normal spark gap sho
u
ld
b
e 1/16" (1.6
mm) - 3/32" 2.4 mm). Electrode sho
u
ld not
b
e mo
v
ed
so far for
w
ard that the pilot flame
w
ill impinge on the
porcelain ins
u
lator. This condition
w
ill ca
u
se the
porcelain to crack and
b
reak off at the point of flame
impingement.