Tankless Water Heater

Overview

A tankless (on-demand) water heater raises water temperature only while water is flowing, eliminating the standby losses of a storage tank. This condensing gas model fires a modulating burner against twin heat exchangers, reaching about 0.96 UEF by recovering latent heat from the flue gas, and adjusts output continuously to hold a stable outlet temperature across a wide range of draw rates.

The unit is built from the Wall-Mount Cabinet, the Heat Exchanger Assembly, the Burner Assembly and its Combustion Fan Assembly, the Water Section, the Sensor Set and Control Board Assembly, plus condensate, venting, remote, and safety subsystems.

How it works

When a hot tap opens, the turbine flow sensor in the Water Section detects the draw and the Control Board Assembly board begins the firing sequence. The Combustion Fan Assembly establishes combustion airflow, the igniter in the Burner Assembly lights the premix gas burner, and a flame-sense rod confirms ignition. The modulating gas valve then trims firing rate against the difference between inlet and outlet thermistor readings in the Sensor Set set.

Combustion gas first heats water in the copper primary section of the Heat Exchanger Assembly, then passes the stainless secondary condensing exchanger, where flue-gas water vapor condenses and surrenders its latent heat. The acidic condensate drains through the Condensate System system, where a neutralizer cartridge raises its pH before disposal.

Cooled exhaust leaves through the concentric Venting / Flue Kit kit, which also draws combustion air. The Safety & Freeze Protection subsystem adds an overheat thermal cutoff and built-in freeze-protection heaters, while a wired remote controller sets temperature and reports faults.