Weil-McLain 80 Boiler For Gas, Light Oil, Gas/Light Oil Fired Burners
16 Part No. 550-141-935/0602
Connect steam boiler piping8
General steam piping information:
• Hartford loop piping arrangement and wet return are
required for steam boilers. Use the Hartford loop for
both pumped-return and gravity-return systems.
• Maintain 24-inch minimum from waterline to bottom
of header (56¼" from bottom of section).
• When using condensate receiver, feed pump must be
energized by boiler-mounted pump controller. Install
piping:
Install piping as shown on pages 16 through 18 for single
boilers. See page 19 for additional requirements when
piping multiple boilers.
Improperly piped systems or undersized
piping can contribute to erratic boiler
operation and possible boiler or system
damage. Piping system must be installed
as shown, using pipe sizes shown. Pipe
sizes shown are for two-pipe, pumped-
return systems. Adjust pipe sizing as
needed when connecting to gravity-
return systems. Consult local Weil-
McLain distributor or sales office before
installing alternate piping.
1. Connect supply and return piping:
a. See Table 8.
1) Size condensate return piping by pump.
2) Size gravity condensate return same as equalizer
“J” pipe size.
b. Install system drain valve in lowest part of return
piping close to boiler. ASME size requirements are
shown in Table 7, page 14.
c. Connect cold water fill piping as shown in Figure 14.
Also shown are recommended valves and water
meter, if used. Water meter will detect added
makeup water, indicating leaks in system.
2. Condensate piping:
a. Satisfactory operation of any steam heating system
depends on adequate return of condensate to
maintain steady water level.
b. Avoid adding excessive amounts of raw make-up
water.
c. Where condensate return is not adequate, a low
water cutoff with pump control, condensate
receiver, and condensate boiler feed pump should
be installed. Refer to page 18, Figure 18 for piping
and Table 9 for sizing.
3. Multiple steam boiler piping
a. See page 19.
Figure 14 Cold water fill piping
Table 8 Steam boiler pipe size for typical 2-pipe steam systems