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The Bradford White
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Introduction
The new Bradford White URG1PV & URG2PV 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, significantly quieter operation, additional vent lengths, and
Bradford White Defender Safety System
®
(not available on all models).
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 Thermostat/Gas Control Valve with LED - was developed for ease of troubleshooting
by providing simple diagnostic codes to pinpoint an installation or component performance issue.
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 free wiring.
Increased Vent Lengths - increased venting performance is achieved while maintaining Energy Factor &
FHR (not applicable on all models) performance.
The URG1PV & URG2PV water heaters use a combustion system where 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
operating parameters exists, the gas control diagnostic LED will flash a code to positively identify an
operational issue.
This service manual is designed to facilitate problem diagnosis and enhance service efficiency. Please read
the service manual completely before attempting service on this new series of power vent models.
How the Safety System Works
During normal operation, most air for combustion is drawn into the water heater through the openings in the
jacket door. This air travels into the burner venturi, mixing with the gas jet. This air is then mixed with gas
inside the burner and drawn to the burner screen and is efficiently combusted producing Ultra Low NOx
emissions. Additional air is drawn through the openings in the jacket. This air travels down and around the
combustion chamber and enters through holes in the bottom of the corrosion-resistant combustion chamber.
The air then travels up through the oriented flame arrestor plate louvers, where they velocity of the air is
increased and its direction altered. The air then mixes in a normal manner with the combustion products
from the burner.
In the case where trace amounts of flammable vapors are present in the air flowing into the combustion
chamber and burner venturi, the vapors are harmlessly ignited by the burner/pilot flame. If flammable vapors
are in sufficient quantity to prevent normal combustion, the burner and pilot flames are designed to shut
down.
Should the flammable vapors continue to the burner, the flame arrestor plate and burner screen prevent the
flames from traveling backwards and igniting vapors outside of the combustion chamber. The gas control
utilizes a flammable vapor sensor to detect the presence of flammable vapors and shut down if the vapors
achieve a certain level.
