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Figure 8 – Cascade Multiple Boilers – Indirect Priority on One
FIGURE NOTES:
1. This drawing is meant to demonstrate system piping concept only.
2. A mixing valve is recommended if the DHW temperature is set above the factory setting of 119
o
F.
3. Install a minimum of 12 diameters of straight pipe upstream of all circulators.
4. Piping shown is Primary/Secondary.
5. System flow (Secondary Loop) must be greater than the boiler’s Primary Loop flow.
6. Installations must comply with all local codes.
7. In Massachusetts, a vacuum relief valve must be installed on the cold water line per 248 CMR.
8. Reference Multiple Boiler Manifold Piping chart, Part 5, Section H.