Installation Manual

WHL-019 REV. 12.17.14

PART 2 – BEFORE YOU START

A. WHAT’S IN THE BOX

Also included with the heater:

 Intake PVC Tee with Screens

 Exhaust PVC Coupling with Screens

 Temperature and Pressure Relief Valve

 Installation Manual

 Warranty

 LP Conversion Kit (Natural Gas Models Only)

 Two Threaded Caps (WGCM Models Only)

B. HOW THE HEATER OPERATES

Modulation Condensing Technology is an intelligent system that delivers highly efficient water heating, while maximizing efficiency

by measuring the data parameters of your water heating system. Some of its features are:

Stainless Steel Water Storage Tank

The stainless steel water storage tank has a combustion chamber submerged into the tank water. When the water heater is fired,

combustion gases heat the combustion chamber walls, transferring heat directly into the surrounding water. These hot gases are blown

into secondary heat exchanger coils, where more heat is transferred into the water, removing even more heat from the gases.

Modulating Combustion System

Modulation during water heating operation is based on tank temperature. The control monitors the system to regulate burner output

during operation to match system demand. This increase in efficiency allows for substantial fuel savings.

Gas Valve

The gas valve senses suction from the blower, allowing gas to flow only if the gas valve is energized and combustion air is flowing.

Upper Supply Tank Sensor

This sensor monitors the upper portion water temperature (system supply) of the water heater. The control module adjusts the burner

firing rate so the outlet water temperature meets the set point.