Part number 550-101-232/0703
9
GAS-FIRED WATER BOILER — Installation Manual — Multiple-boiler Systems
06-24-03 CONFIDENTIAL REVIEW & COMMENT ONLY
Figure 8 Piping schematic — Typical piping for multiple Ultra boilers, using Weil-McLain Easy-Fit
®
Manifolds
1 Flow/check valve (each boiler)
2 Isolation valves (when used)
3 Cap
4 Easy-Fit
®
Manifold (supply), sized per Fig. 6
or Fig. 7, page 8
5 Easy-Fit
®
Manifold (return), sized per Fig. 6
or Fig. 7, page 8
6 Primary circulator
7 Expansion tank (diaphragm type)
8 System air eliminator
9 System automatic air vent
10 Pressure reducing valve
11 Check valve or backflow preventer, as
required by applicable codes
12 Isolation valve
13 Cold water supply
14 Supply water temperature control (when
used)
15 Low water cutoff (when used) (place above
primary header)
16 Water flow switch (when used)
17 Boiler circulator (each boiler)
18 System supply
19 System return
20 Boiler relief valve and discharge piping, installed
per Ultra Boiler Manual
This manual provides general guidelines for piping and installation. Your installation must comply with all applicable local
codes.
When using isolation valves on each boiler, some codes may require providing a low water control and additional
limit for each boiler. If desired, consult the codes to determine if exclusion of the individual boiler isolation valves
may allow the use of a single water level control and additional limit for the entire multiple boiler system.
