SECTION 1
8
: D
IRECT
F
IRED
B
URNER
59
FIGURE 2
8
: HMA-2A Burner
1
8
.1 Direct Fired Burner I
g
nition
The b
u
rner that is
u
sed in the Rapid Engineering
LLC
u
nit is eq
u
ipped
w
ith a pilot assembly. The pilot
assembly consists of a pilot gas t
u
be, spark
electrode or rod and a flame rod
w
ith gro
u
nding
assembly. For proper ignition the spark rod m
u
st be
adj
u
sted correctly. A high
v
oltage arc is generated
bet
w
een the spark rod and the pilot gas t
u
be. The
gas flo
w
ing o
u
t the ports in the pilot gas t
u
be is
ignited by this arc. The arc
w
ill be a brilliant electric
bl
u
e in color.
See Page 59, Figure 28
.
FIGURE 29: Spark Rod Dimensions
The gas s
u
pplied to the pilot gas t
u
be sho
u
ld be 3 1/
2"
w
c for nat
u
ral gas and bet
w
een 9 to 11"
w
c for
propane or LP. The difference bet
w
een the t
w
o f
u
els
is that a restricting orifice is installed in the propane
or LP pilot gas t
u
be. The pilot assembly can be
u
sed
on propane or LP
w
itho
u
t an orifice, if this is the case
then the press
u
re for LP is 2.0"
w
.c. Ignition
w
ill take
place
w
ith the introd
u
ction of gas to the pilot gas
t
u
be. The pilot flame
w
ill be mostly bl
u
e in color
w
ith
streaks of yello
w
. The flame size
w
ill be ro
u
ghly 2" in
diameter. The flame m
u
st be steady and consistent
in size.
B
C
E
D
A
WARNING:
the ignition system on the air handler generates bet
w
een 6,000 to 10,000
v
olts.
A
B
C
D
E
in
2.940
0.125
0.125
1.881
0.633
cm
7.468
0.318
0.318
4.778
1.608
