Bradford-White Corp UTW450S60FR*N Manual De Usuario

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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. 

To further promote quicker service times the new gas valve can be removed and replaced with-

out draining the water heater.  A special tool is required and will be provided with each gas 

valve kit shipped from our Service Parts department.   
Please read the service manual completely before attempting service on this new series of 

power

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 effi-

ciently 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 the 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.  This causes the thermopile to overheat and shuts down the main pilot and burner. The 

thermopile powers the intelligent diagnostic control which is capable of recognizing restricted 

airflow conditions caused by severe lint, dust and oil accumulation on the burner screen and 

arrestor plate. The intelligent diagnostic control will deactivate the burner and pilot in the 

unlikely event of restricted airflow.

It is intended for this manual to be used by qualified service personnel for the primary purpose 

of troubleshooting and repair of the Bradford White Residential Flue Damper water heaters. 

Understanding the sequence of operation section of this manual will contribute greatly to trou-

bleshooting the water heater. 

The Honeywell WV4460E Electronic Gas Control will display error codes in the event of ab-

normal operation. Error codes are listed in the troubleshooting chart beginning on page 13 of 

this service manual. The troubleshooting chart will also indicate the probable cause for the error 

code and direct the service professional to a service procedure to properly diagnose the abnor-

mal operation. 

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