Installation Instructions

whl-590 Rev. 003 Rel. 003 Date 3.22.18

RECIRCULATION

COLD WATER INLET

HOT WATER OUTLET

NOTES:

1. Minimum pipe size should match connection size. Upsize pipe accordingly if greater ow is required.

2. A thermal expansion tank suitable for potable water must be sized and installed within this piping system between the backow preventer

and the cold water inlet.

3. All circulators should have an integral ow check.

4. Drains and check valve between water heater and piping will assist in purging air from system.

5. These drawings are meant to demonstrate system piping only. The installer is responsible for all equipment and detailing required by local

codes. In Massachusetts, you must install a vacuum relief valve per 248 CMR.

6. Mixing valve application is optional, but recommended to help prevent scalding.

7. Always shut o power to the water heater or isolate the heater from the system if ANY plumbing work is to be done. Running the water

heater without water will result in dry-ring.

NOTE: These drawings are meant to show system piping concept only. Installer is responsible for all equipment and detailing required by

local codes.

Figure 9 - DHW Piping, Single Water Heater - NOTE: There is a Built-In Flow Check in the Internal Pump Loop