User Guide

Part number 550-100-325/0718
43
AquaBalance
®
SERIES 2 WALL MOUNT GAS-FIRED WATER BOILER — Boiler Manual
18 Multiple boiler installations (continued)
Figure 54 Piping schematic –– typical piping for multiple AquaBalance
®
Heating Only boilers
Legend for Figure 54
1 Flow/check valve
2 Isolation valves (when used)
3 Cap
4 Primary circulator
5 Expansion tank (diaphragm type)
6 System air eliminator
7 System automatic air vent
8 Pressure reducing valve
9 Check valve or backflow preventer, as required by appli-
cable codes
10 Cold water supply
11 Supply water temperature control (when used)
12 Low water cutoff (when used) (place above primary
header)
13 Water flow switch (when used)
14 Boiler circulators
15 System supply
16 System return
17 Boiler P/T gauge (field supplied), relief valve and discharge
piping, installed per this manual.
18 Purge/drain valve