A.O. Smith TC-049R3 Service Handbook page 5

RESIDENTIAL GAS AND ELECTRIC WATER HEATER
of (120° F, 49°C) water weighs approximately 8.25 pounds.
One gallon
= (Mixed Temp. – Cold) divided by (Hot Temp. – Cold)
% of Hot
General Section – continued
% Thermal Efficiency
= GPH X 8.25 X Temp. Rise X 1.0
BTU Output
= (BTU/H Input X % Eff.) divided by (Temp. Rise X 8.25)
GPH
of Natural Gas contains about 1000 BTU of heat.
One cubic foot
is equal to 100,000 BTU
One "therm"
of Propane Gas contains about 2500 BTU of heat.
One cubic foot
of Propane gas contains about 91,250 BTU of heat.
One gallon
of Propane gas contains about 21,600 BTU of heat.
One pound
One pound of gas pressure is equal to 27.7 inches water column pressure
Centimeters = Inches X 2.54
MM (millimeters) =Inches X 25.4
Meters = Inches X .0254
Doubling the diameter of a pipe will increase its flow capacity (approximately) 5.3 times.
CONSTRUCTION:
The inside of the tank is constructed of a
to metal contact and rusting of the tank.
An will be installed within the tank. The hex-head plug end of the anode is visible on
anode rod
the top of the water heater. This metal rod offers secondary protection of the tank against
corrosion where the application of glass is not possible (threaded tank openings). These areas
will have small areas of water to metal contact.
All water heaters will contain at least
(to prevent water temperatures approaching the "steam" level).
limit
A.O. Smith Water Products Company
©2005
SERVICE HANDBOOK
Pounds X .45359 = Kilogram
Gallons X 3.7854 = Liters
= (GPH X 8.25 X Temp. Rise X 1.0) divided by BTU/H Input
Inches of Water Column X .036091 = PSI
Inches of Water Column X .073483 = Inches of Mercury (Hg.)
is constructed of steel.
Tank
glass lining
one thermostat
bonded to the steel. This prevents water
(to operate the heater) and
Technical Training Department
4
one high
Ashland City, TN