Westinghouse WBRU 80W Series Installation, Start-Up And Maintenance Instructions page 37

37
Figure 23 – Zoning with Pumps and Indirect Fired Water Heater – Direct Piping
NOTES:
1. This drawing is meant to show system piping concept only. Installer is responsible for all equipment and detailing required by local
codes.
2. All closely spaced tees shall be within 4 pipe diameters center to center spacing.
3. A minimum of 6 pipe diameters of straight pipe shall be installed upstream and downstream of all closely spaced tees.
4. The minimum pipe size of DHW piping should be ¾" diameter. See Table 16 for minimum CH pipe sizing.
5. Circulators are shown with isolation flanges. The alternative is standard flanges with full port ball valves. Purge valves can be used
with circulator flanges as an alternative.
6. Install a minimum of 12 diameters of straight pipe upstream of all circulators.
7. VERY IMPORTANT – Minimum flow rates outlined in this manual must be maintained through the heat exchanger to minimize short
cycling.
8. Each heating zone of a pump-based system has its own circulator with turns on when a zone thermostat calls for heat.
9. Install a check valve on the return line to the boiler.
WHL-032 REV. 6.2.16