L & H Electric Ranges

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ELECTRICS WATER HEATERS
Correct Application of Water Heaters
IN THE installation of any type of heater it should be borne in mind that a material drop in temperature of 6 to 15 degress may occur in a relatively short length of pipe. In order to reduce this loss to a minimum, hot water pipes should be lagged in the same manner that the tank is to retain all the heat which makes it unnecessary to waste a large quantity of water before sufficient hot water reaches the user. The average temperature at the top of the tank is 160 degrees; to the quantity of hot water at tank temperature to be used there will be added an equal quantity, if not more, of cold water. Consequent¬ ly when determining the quantity of water to be used for a given purpose it must be borne in mind that the quantity of water actually heated may be considerably less than the total quantity required, since it is heated initially to a higher temperature than can be used. For determining the amount of electricity required for heating a given quantity of water the following must be known:
Capacity of Tan\.
Time required for raising temperature from minimum to maximum; that is, temperature of water entering the tank and temperature of water leaving the tank.
If tan\ is insulated, what is the thic\ness and kind of in¬ sulation, as there is some loss in the tank itself and in the insulation surrounding it.
With these factors known, it can be figured from the following formula:
The amount of heat necessary to raise the tempera^ ture of one pound of water one degree Fahrenheit is one B.T.U. (British Thermal Unit). One \ilo^ watt hour of electricity generates 3,412 B.T.U.'s.
Therefore, assuming that the water enters the tank at 60 degrees Fahrenheit and that it is to be delivered at 160 degrees Fahrenheit inasmuch as a raise of 100 degrees in temperature or 100 B.T.U.'s are necessary to raise the temperature of one pound of water 100 degrees Fahrenheit; since a gallon of water weighs approximately 8 1/3 pounds, it will necessitate 833 B.T.U.'s to raise one gallon of water 100 degrees Fahrenheit.
From the above we see that one kilowatt of electricity flowing for one hour generates 3412 B.T.U.'s and one watt (which is 1/1000 of a kilowatt), will generate 3.412 B.T.U.'s. If we divide 833 B.T.U.'s necessary to raise the temperature of one gallon of water 100 degrees Fahrenheit by 3.412 B.T.U.'s which are generated by one watt of electricity in one hour, we note the answer is 244, which is the watts necessary to raise the temperature of one gallon of water 100 degrees Fahrenheit or approxi¬ mately ]/4 kilowatt hour. If only a fifty degree rise in temperature is required, then the amount of current necessary is one-half, or one-eighth kilowatt hour.
This is not taking into consideration any losses. In our model No. 1253 Storage Type Heater the losses are 3 K.W. hours per day of twenty-four hours. In other words if fifty-three gallons of water had been heated to 160 degrees and no water is drawn off it will take 3 kilowatt hours to maintain that temperature. This, on a 3-cent rate would mean 9 cents per day radiation losses plus 14 cent per gallon for each gallon of water used.
On model No. 1225 Heater the losses are 2 K. W. per day. On our No. 1210 Heater the losses are 2.7 K.W. per day. The reason for the low loss per gallon on the model No. 1253 is due to the fact that there are 4|/2 inches of insulation. The higher loss in the model No. 1210 is due to the fact that there are more square feet of surface exposed per gallon capacity than on either the No. 1225 or No. 1253.
Side Arm Circulating Type
Note goose neck trap on hot water line.
Installation of circulating type. All hot water pipes and tank should be insulated with an ap¬ proved insulating: ma¬ terial.
The circulating type water heaters are made of brass and copper, attractively finished in gray lacquer and thorough¬ ly insulated with wool felt. The unit is nickel chromium ribbon, mica insulated. For each inch of lineal unit, 1% square inches of surface are exposed so that the unit operates at an extremely low density. The wiring is in rigid conduit.
Heaters work equally well on direct or alternating current and  are  not affected  by frequency  or  voltage  changes.
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