HTP Mod Con 300 VWH, Installation And Maintenance Instructions Manual

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LP- 276 REV. 9.4.14
Figure 10
NOTES:
1. This drawing is meant to demonstrate system piping concept only. Installer is responsible for all equipment and detailing required by local codes.
2. Boiler circulator(s) must be rated for open loop applications. Do not use cast-iron circulators.
3. Boiler circulator(s) operate continuously.
4. The minimum pipe size for connecting to a water storage tank is 1 ½”.
5. The minimum pipe size for connecting the boiler is 1 ½” for the Mod Con 300 VWH and 2” for the 500 and 850 models.
6. All pumps are shown with isolation flanges or full port ball valves for isolation. The alternative is standard flanges with full port ball valves and a
separate flow check valve.
7. Install a minimum of 12 diameters of straight pipe upstream of all circulators and check valves.
8. Install a vacuum relief valve in accordance with local code requirements.
9. Multiple boilers and storage tanks shall be installed with reverse return piping (as shown).
10. Mixing valves are recommended on all tanks if hot water temperature is above 119
o
F.
11. Expansion tank must be rated for use with potable water.
12. Use either indirect/tank sensor or system/pipe sensor mounted on common return to the boiler.
13. Wire the tank or system/pipe sensor connected to the DHW sensor terminals on the follower boiler addressed as #1.
14. The system/pipe sensor must be placed on common piping to the tank, as close to the tank as possible.
15. The system/pipe sensor is wired to the system sensor terminals on the master boiler.