![background image](http://html1.mh-extra.com/html/ibc/ex-series/ex-series_installation-and-operating-manual_3219333051.webp)
Closely-spaced tees: To avoid induced flow, install each set of tees with straight piping a minimum
of 8 pipe diameters upstream and 4 pipe diameters downstream. Avoid using elbow or other
component that may create turbulent flow. Position tees as close together as possible (maximum 4
pipe diameters apart) and ensure that there are no restrictions between the fittings that would result
in a pressure drop.
Heat migration: On secondary loops that extend vertically to a load that is above the primary loop,
steps must be taken such as fabricating a thermal trap in the return piping - minimum 18" (46 cm)
drop - to prevent thermal siphoning and heat migration to the load when there is no demand for heat
to that loop. Alternatively, use check valves on both supply and return of secondary piping.
Figure 27
Important Primary/Secondary piping details with closely-spaced tees
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3.8.2 System piping