Bradford White EVERHOT IGI-180C Series Installation And Operating Instruction Manual page 17

Recommended Piping for Power Failure Freeze Protection
As long as electrical power and gas are supplied to the EVERHOT® water heater, freeze protection is
provided to the heat exchanger and piping inside the water heater with ambient temperatures as cold as
-30°F (-34°C), when protected from direct wind exposure. In the event of a power failure with ambient
temperatures below freezing, the water heater must be drained of all water to prevent freeze damage.
The water heater may be drained manually, or automatically, through the installation of the optional
solenoid valves as shown in the following illustration. The drain solenoids are recommended for very cold
climates to prevent water heater freeze damage where power failures from ice and windstorms occur.
The electrical connections for the two solenoids must be tied to the 120 volt main power supply (black
and white wires). When the electrical power to the water heater fails, the ¾" solenoid on the cold water
inlet pipe closes, stopping water flow into the water heater. The ¼" solenoid opens, allowing the water
heater and connected piping to drain. Make sure the piping from the drain solenoid is run to a suitable
drain or outside the building to prevent water damage.
Drain Solenoid Piping (Fig. 3)
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