American Water Heater 74 Gallon 75100 BTU UltraLow Nox High Recovery Natural Gas Water Heater UBG6275T75S4NV user manual

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PRINTED IN U.S.A. 1112 PART NO. 325321-000
PLACE THESE INSTRUCTIONS ADJACENT TO HEATER
AND NOTIFY OWNER TO KEEP FOR FUTURE REFERENCE.
RESIDENTIAL ULTRA LOW NOx GAS WATER HEATER
•  INSTALLATION   •   OPERATION   •   SERVICE   •   MAINTENANCE  • 
  CAUTION
TEXT PRINTED OR OUTLINED IN RED CONTAINS INFORMATION 
RELATIVE TO YOUR SAFETY. PLEASE READ THOROUGHLY 
BEFORE INSTALLING AND USING THIS APPLIANCE.
LOW LEAD
CONTENT 

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FOREWORD
The design of these models comply with the current edition of ANSI 
Z21.10.3/CSA 4.3 an automatic storage water heater.
Installation diagrams are found in this manual.  These diagrams will serve 
to provide the installer with a reference for the materials and method of 
piping necessary.  It is highly essential that all water and gas piping be 
installed as shown on the diagrams.
In addition to these instructions, the equipment shall be installed in 
accordance with those installation...

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GENERAL SAFETY 

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GENERAL SAFETY 
INFORMATION
PRECAUTIONS
DO NOT USE THIS WATER HEATER IF ANY PART HAS BEEN UNDER 
WATER. Immediately call a qualifi ed service technician to inspect the 
water heater and to replace any part of the control system and any gas 
control which has been under water.
IF THE UNIT IS EXPOSED TO THE FOLLOWING, DO NOT OPERATE 
HEATER UNTIL ALL CORRECTIVE STEPS HAVE BEEN MADE BY A 
QUALIFIED SERVICEMAN.
1. EXTERNAL FIRE.
2. DAMAGE.
3.  FIRING WITHOUT WATER.
4. SOOTING.
Heater must be protected from...

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CHEMICAL VAPOR CORROSION
 WARNINGCORROSION OF THE FLUEWAYS AND VENT SYSTEM MAY OCCUR IF 
AIR FOR COMBUSTION CONTAINS CERTAIN CHEMICAL VAPORS.  SUCH  
CORROSION MAY RESULT IN FAILURE AND RISK OF ASPHYXIATION.
Spray can propellants, cleaning solvents, refrigerator and air conditioning 
refrigerants, swimming pool chemicals, calcium and sodium chloride (water 
softener salt), waxes, and process chemicals are typical compounds which 
are potentially corrosive.  Do not store products of this sort near the...

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CIRCULATING PUMP
A circulating pump is used when a system requires a circulating loop or 
there is a storage tank used in conjunction with the heater.  Refer to the 
piping diagrams at rear of manual for electrical hookup information and 
install in accordance with the current edition of the National Electrical 
Code ANSI/NFPA No. 70.
Only all bronze circulating pumps are used with commercial water 
heaters. Although circulators are oiled and operated by the manufacturer 
some circulators must be oiled...

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CAUTION: IF BUILDING COLD WATER SUPPLY HAS A BACK-FLOW
PREVENTER, CHECK VALVE OR WATER METER WITH CHECK 
VALVE, AN EXPANSION TANK MUST BE PROVIDED.
FIGURE 2.
CIRCULATING RETURN LINE CONNECTIONS
TEMPERED WATER LOOP, IF USED, CONNECT TO POINT A.  
STORED TEMPERATURE WATER LOOP, IF USED, CONNECT TO 
COLD WATER INLETWARNING
TEMPERATURE SETTING SHOULD NOT EXCEED SAFE 
USE TEMPERATURE AT FIXTURES.  SEE TEMPERATURE 
REGULATION ON PAGE 11.  IF HIGHER PREHEAT 
TEMPERATURES ARE NECESSARY TO OBTAIN 
ADEQUATE...

8 fuel burning equipment.  This practice is prohibited by many local  
building codes as is the practice of venting gas fi red equipment to 
the duct work of ventilation systems.
•  Where a separate vent connection is not available and the vent 
pipe from the heater must be connected to a common vent with an 
oil burning furnace, the vent pipe should enter the smaller common 
vent or chimney at a point above the large vent pipe.
FIGURE 3.
VENT CONNECTION
Vent connections must be made to an adequate stack...

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TABLE 4. GAS SUPPLY LINE SIZES (IN INCHES)*
Water Temperature °FTime for 1st Degree Burns
(Less Severe Burns)Time for Permanent Burns
2nd & 3rd Degree
(Most Severe Burns)
110 (normal shower temp.)
116 (pain threshold)
116 35 minutes 45 minutes
122 1 minute 5 minutes
131 5 seconds 25 seconds
140 2 seconds 5 seconds
149 1 second 2 seconds
154 instantaneous 1 seconds
(U.S. Government Memorandum, C.P.S.C., Peter L. Armstrong, Sept. 15, 1978)
HOT WATER
OUTLET
TO TANK
INLET CHECK
VA LV EMIXING
VA LV E COLD...

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PURGING
Gas line purging is required with new piping or systems in which air has 
entered.
  CAUTIONPURGING SHOULD BE PERFORMED BY PERSONS EXPERIENCED 
IN THIS TYPE GAS SERVICE. TO AVOID RISK OF FIRE OR 
EXPLOSION, PURGE DISCHARGE MUST NOT ENTER CONFINED 
AREAS OR SPACES WHERE IGNITION CAN OCCUR. THE AREA 
MUST BE WELL VENTILATED AND ALL SOURCES OF IGNITION MUST 
BE INACTIVATED OR REMOVED.
GAS METER SIZE — NATURAL GASES ONLY
Be sure the gas meter has suffi cient capacity to supply the full rated gas...