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Introduction
The new Bradford White PDX2 and PDX 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,s ignificantly quieter
operation, additional vent lengths and certified FVIR technology.
Spark to Pilot Ignition System -employing the spark to pilot ignition system promotes
reliable and consistent pilot and main burnerignitions 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.
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 & FHSR performance.
The PDX2 and PDX water heaters use a combustion system were flue gases are combined with
dilution air to reduce the flue gas temperature in theblower, combustion air and dilution air are
drawn from outside the building. 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 pressu re 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 acode
to positively identify an operational issue.
This service manual is designed to facilitate problem diagnosisand enhance service efficiency.
To further promote quicker service times the new gas valve can be removed and replaced
without draining the water heater. A special tool is required and will be provided with each gas
valve kit shipped from our Service Partsde partment.
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,air for combustion is drawn into the water heater though the vent pipe from outside your
building. Theair travels into the closed combustion chamber. Theair then mixes with in a normal manner with
supplied gas and its efficiently combusted, producingvery low NOx emissions.
In theunlikely event trace amounts of flammable vapors arepresent in the area surrounding the water heater, the
sealed combustion system preventsthe flammable vapors from reaching the ignition source. Inaddition the
flammable vaporssensor will stop the water heater from operating if a significant amount of flammable vapors are
present.
PDX Series
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