A.O. Smith TC-092 user manual

Summary of the content on the page No. 1

SERVICE
INFORMATION
GUIDE

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FORMULAS & FACTS FORMULAS & FACTS BTU (British Thermal Unit) is the heat required to raise 1 pound of water 1°F 1 BTU = 252 cal = 0.252 kcal 1 cal = 4.187 Joules BTU X 1.055 = Kilo Joules BTU divided by 3,413 = Kilowatt (1 KW) FAHRENHEIT CENTIGRADE 32 0 41 5 60.8 16 To convert from Fahrenheit to Celsius: 120.2 49 (°F – 32) x 5/9 or .556 = °C. 140 60 180 82 212 100 One gallon of 120°F (49°C) water BTU output (Electric) = weighs approximately 8.25 pounds. BTU Input (Not exactly true due to mi

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FORMULAS & FACTS FORMULAS & FACTS GPH (Gas) = One gallon of Propane gas contains (BTU/H Input X % Eff.) divided by about 91,250 BTU of heat. (temp. rise x 8.25) One pound of Propane gas contains GPH (Electric) = about 21,600 BTU of heat. (KW x 3413) divided by (temp. rise x 8.25) or (KW x 414) One pound of gas pressure divided by (temp rise.) is equal to 27.7 inches water column pressure KW required = Inches of Water Column (GPH X 8.25 X temp. rise) x .036091 = PSI divided by 3413 or Inche

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COMMON TERMS COMMON TERMS Draw efficiency is the quantity of hot water available to the consumer before the outlet water temperature decreases 25°F. A 40-gallon water heater will typically provide 70% (28 gallons) within this temperature range. The burner or elements are allowed to operate during this test. Incoming, cold water mixes the remaining stored water below this 25° limitation. Energy factor is an indicator of the combined thermal efficiency and standby efficiency of a water heater.

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COMMON TERMS COMMON TERMS The closed system illustrated requires the thermal expansion tank because of the preceding #2 and #3 facts. 4 Gases in the water will separate from the water as temperature rises. 5 Water boils at 212°F – at sea level – unless it is contained under pressure. At 52 psi gauge pressure, water would not boil until it exceeded 300° F. 6 Minerals in the water will separate from the water as temperature is added. This may lead to a much faster scaling rate in the tank. Ex: 10

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COMMON TERMS COMMON TERMS Polarity – Verify that an electrical socket has correct “polarity.” Verify that the “Neutral” (typically white on a 120V circuit) wire has no power to ground and that the “Hot” (typically black wire on a 120V circuit) has 115 – 125V to ground. Watts divided by Volts = Amps (single phase) Volts x amps = watts. (Watts x .557) divided by Volts divided by amps (Volts) = Amps (3 phase) = ohms (resistance) For insulating purposes “R” value is a measure of the resistance

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A. O. SMITH TRAINING CENTER 106 Adkisson Street Ashland City, TN 37015 www.hotwater.com