LGB
Gas-Fired Boiler — Boiler Manual
Part Number 550-141-186/0100
18
Install piping
Pipe the header at least 24 inches above the boiler water line.
Weil-McLain recommends using a boiler feed system, with the pump operated by a level
controller on the boiler. Weil-McLain does not recommend using a condensate return system
on which the pump is operated by a receiver-mounted float switch. Level controls (
Section
6
) must be mounted on same side of boiler as the return piping and equalizer.
Install a blowdown valve in tapping
C1
or
C2
(see
Figures 11a and 11b
, pages 12 and 13),
sized per ASME Code:
Models LGB-4 through LGB-12
— use 1" blowdown valve.
Models LGB-13 through LGB-23
— use 1¼" blowdown valve.
See
Figure 20
, Page 20, for multiple steam boiler piping.
Figure 17
Steam boiler piping for
LGB-4 through LGB-12
(single riser)
Figure 18
Steam boiler piping for
LGB-13 through LGB-23
(riser each end)
3b
Piping
steam boilers
Improper piping systems and/or undersized piping can contribute to erratic
boiler operation and possible boiler damage. The piping must be installed
as illustrated, using the recommended minimum pipe sizes.
Minimum Recommended Pipe Sizes
Boiler
Model
Number
Riser Header Equalizer
A
H
J
LGB-4 —
LGB-8
4"
4"
2"
LGB-9 —
LGB-11
5"
5"
2
1
/
2
"
LGB-12
6"
6"
2
1
/
2
"
Minimum Recommended Pipe Sizes
Boiler
Model
Number
Risers
Header Equalizer
A
B
H
J
LGB-13 —
LGB-15
4"
4"
6"
4"
LGB-16 —
LGB-19
5"
5"
6"
4"
LGB-20 —
LGB-23
6"
6"
8"
4"
186-17
Condensate return
A
H
Steam supply
J
J
J
J
1
2
Reducing from header
to equalizer - alternate
piping methods.
DO NOT reduce the
header in the
horizontal piping.
1
OR
186-17a
Water line
Water line
Hartford loop tee
Use only close nipple
or street ell here.
Floor line
Boiler
Header
Steam
supply
24"
min
4"
33 7/16"
2
186-17b
Condensate return
A
H
Steam
supply
B
1
J
J
J
J
2
186-18
