Installation Instructions
whl-590 Rev. 003 Rel. 003 Date 3.22.18
24
WATER HEATER
HOT WATER OUTLET
COLD WATER INLET
AIR SEPARATOR
OFF OFF OFF OFF OFF
DIFFERENTIAL
PRESSURE
SPACED TEES
LEAD FREE
Figure 16 - Water Heater Installed with Combi Appliance - NOTE: There is a Built-In Flow Check in the Internal Recirculation Pump Loop
NOTE: The solenoid valve is powered by the water heater. The solenoid valve must be normally closed, energize when the water heater is over
90% of capacity, and deactivate when water heater is less than 50% of capacity.
NOTE: When a water heater is installed with a combi appliance, ensure Installer Parameter 19:SU is set to Cd – Comfort Mode. This is the
default mode of operation. Also wire the solenoid as described in Figure 16. Failure to do so will result in improper appliance operation.
NOTE: Ensure the DHW temperature setting is the same on the water heater and the combi appliance. Failure to do so will result in improper
appliance operation.
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 backow 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.