Bradford White UPDX series, Service Manual

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UPDX Series
Introduction
The new Bradford White UPDX2 water heaters are designed to provide reliable performance
with enhanced standard features
. New design features include reliable spar k to pilot ignition
system, enhanced diagnostics, simplified servicing, significantly quieter operation, additional
vent lengths, certified FVIR technology and Ultra Low NOx emissions
.
S pa r k to P i lot Ign i t i on S y s t e m - E mploying the spar k to pilot ignition system promotes
reliable and consistent pilot and main burner ignitions to provide hot water on demand .
Int e g r at e d Imm ersi on Th er mo s tat/Ga s Cont r ol Valv e w i th LED - Was developed for ease
of troubleshooting by providing simple diagnostic codes to pinpoint an installation or
component performance issue
.
Pow er ful Blow er
- Will eliminate problems with difficult venting situations .
Qu ie t er and Cool er Blow er Op er at i on - Blower noise is significantly reduced for both
interior and exterior environments . Cooler operation increases blower life by reducing bearing
wear and noise .
Rugg e d W iri ng Conn e ct i on s - Receptacle type connections promote error free wiring .
Inc re a se d V e nt L e ngth s
- Increased venting performance is achieved while maintaining
E nergy Factor & First Hour Supply performance .
The UPDX2 water heaters use a combustion system where flue gases are combined with
dilution air to reduce the flue gas temperature in the blower, 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 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 L E D will flash a code
to identify an operational issue .
This service manual is designed to facilitate problem diagnosis and enhance service efficiency .
To further promote quic k er service times the new gas control can be removed and replaced
without draining the water heater . A special tool is required and will be provided with each gas
valve k it shipped from our Service Parts department .
Please read the service manual completely before attempting service on this new series of
power direct vent models
.
How the Safety System Wor k s
During normal operation, air for combustion is drawn into the water heater through the inta k e
vent pipe from outside your building . The air travels into the closed combustion chamber . The
air then mixes in a normal manner with supplied gas and is efficiently combusted, producing
Ultra Low NOx emissions
.
In the unli k ely event trace amounts of flammable vapors are present in the area surrounding the
water heater, the sealed combustion system prevents the flammable vapors from reaching the
ignition source
. In addition the flammable vapor sensor will stop the water heater from
operating if a significant amount of flammable vapors are present .
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