should be metallic pipe or a high temperature plastic pipe (CPVC, etc.) to insure that hot water flow will not damage the discharge piping from the relief valve.
Water heater maintenance includes periodic tank flushing, cleaning and removal of lime scale from the heating elements. Where used, the water heating system circulating pump should be oiled.
CAUTION: Avoid contact with hot discharge water. Insure that no one is in front of or around the relief valve discharge line. Make sure that the extremely hot water manually discharged from the relief valve will not cause bodily injury or property damage.
WATER CHEMISTRY
In hard water areas, water treatment should be used to reduce the introduction of minerals to the system. Minerals in the water can collect in the storage tank and on the immersion heating elements causing noise on operation. Excessive build up of minerals on the surface of the heating elements can reduce the service life of the elements and lead to a
Proper operation of this electric water heater is based on heating potable water with a hardness of 5 to 25 grains per gallon and a total dissolved solids not exceeding 350 PPM. Consult the manufacturer when heating potable water exceeding these specifications. Heating of high hardness and/or high total dissolved solids water may require frequent cleaning of the storage tank and heating elements to achieve proper operation. The higher the level of dissolved solids or water hardness, the faster the dissolved minerals in the water will precipitate out and form scale deposits on the heating elements and in the storage tank. The level of scale formation is also accelerated as stored water temperature increases. Water with a hardness of less than 5 grains per gallon will usually have a low pH which can be aggressive and corrosive causing
FLUSHING THE STORAGE TANK
1.Turn off main power at the electrical disconnect switch.
2.Open the drain valve. Allow water to flow until it runs clean.
3.Close the drain valve when finished flushing.
4.Turn on the electrical disconnect switch (after filling).
SEDIMENT REMOVAL
Water born impurities consist of dissolved minerals which precipitate out of the heated water and fine particles of soil and sand which settle out and form a layer of sediment on the bottom of the tank. In time, if not removed, the level of sediment might reach the heating elements.
For convenience, sediment removal and element lime scale removal should be performed at the same time as follows:
Sediment and Lime Scale Removal
Sediment and lime scale accumulation on the heating elements is a normal condition common to all immersion type elements. Factors which affect the amount of this formation are:
1.Amount of hot water used. As the volume of water increases, more scale results.
2.Water temperature. As the temperature of the water is increased, more scale is deposited on the elements.
3.Characteristics of water supply. Regardless of water treatment, the elements should be examined regularly.
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