Bradford White U-TW4-75S-76R-3N - Manual (Page 5)

Page 5
The Bradford White ECO-DEFENDER Safety System
®
The Bradford White ECO-DEFENDER Safety System was designed to resist
the ignition of flammable vapors that can occur outside of the water heater
and produce Ultra Low NOx emissions. Use and installation are nearly
identical to previous versions of atmospherically fired and vented water
heaters. A number of exclusive design features are incorporated in the
system that will require additional knowledge on the part of the qualified
service provider. The following information will instruct service professionals
on the function, proper diagnosis, and repair of water heaters employing
the Bradford White ECO-DEFENDER Safety System.
Introduction
The new Bradford White TTW ECO-DEFENDER water heaters are designed to provide
reliable performance with enhanced standard features. New design features include reliable
spark to pilot ignition system, enhanced diagnostics, simplified servicing, quiet operation,
additional vent lengths, Bradford White ECO-DEFENDER Safety System ® and Ultra Low
NOx emissions.
Spark-to-Pilot Ignition System - Employing the spark-to-pilot ignition system promotes
reliable and consistent pilot and main burner ignitions to provide hot water on demand.
Integrated Immersion Thermal Well/Gas Control with LED - Was developed for ease of
troubleshooting by providing simple diagnostic codes to pinpoint an installation or component
performance issue.
New Powerful Blower - Will eliminate problems with difficult venting situations.
Quieter and Cooler Blower Operation - Blower noise is significantly reduced for both
interior and exterior environments. Cooler operation increases blower life by reducing bearing
wear and noise.
Rugged Wiring Connections - receptacle type connections promote error free wiring.
Increased Vent Lengths - Increased venting performance is achieved while maintaining
Energy Factor and FHSR performance.
The TTW1 (U1TW & U4TW), TTW2 (U2TW) & UTW4 water heaters use a combustion
system were flue gases are combined with dilution air to reduce the flue gas temperature in the
blower. The diluted flue gases are evacuated to the exterior through low temperature vent
materials. The gas control maintains water temperature, ignition sequence and regulates gas
flow. A safety circuit consisting of a pressure switch and blower temperature switch verifies
proper conditions exist for safe and reliable operation. If a situation outside of normal
Introduction
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