Bradford White EverHot TGHE-160I-NX Installation And Operation Instruction Manual page 21

Note: in Massachusetts, the following must be done:

Tempered potable water must meet temperatures in 248 CMR.

All water piping must be insulated in accordance with 780 CMR (Massachusetts energy code).

50 feet maximum distance from water heater to space heating load (developed length).

Piping loop between water heater and heating load must be in compliance with 248 CMR.

All circulators must use an electronically controlled timer that activates every 6 hours for 60 seconds.
Figure 7. Recommended Piping for Combination Water and Space Heating Applications.
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