The effect of hard water scale buildup and water treatment on residential water heater performance

Conference · Wed Jan 01 00:00:00 EST 1986 · ASHRAE Trans.; (United States)

OSTI ID:6457988

Talbert, S G; Stickford, G H; Newman, D C; Stiegelmeyer, W N

Conventional gas and electric storage-type residential water heaters were operated at four different U.S. cities under accelerated test conditions to measure the effect of scale buildup on efficiency and to assess the benefits and limitations of common water treatment methods. The four selected test sites had hard water supplied with expected scale-forming tendencies and were located in Columbus, OH; Lisle, IL; Roswell, NM; and Marshall, MN. The main conclusions are as follows. After 60 lbs (27 kg) of scale buildup at two of the test sites (representing an estimated 20 years of equivalent scale buildup), the efficiency of the gas water heaters gradually declined about 5%, while that of the electric water heaters remained constant. However, the buildup of scale in the electric heaters caused the electric heating element to fail periodically, and in the gas-fired heaters, it caused the tank metal temperatures near the burner to operate hotter. Treated water (either softened, softened plus polyphosphate, or hard plus polyphosphate) effectively reduced scale buildup and tended to reduce the corrosion rates of the metal test coupons in hot water.

• Research Organization: Battelle Columbus Div., Columbus, OH
• OSTI ID: 6457988
• Report Number(s): CONF-8606125-
• Journal Information: ASHRAE Trans.; (United States), Vol. 92:2B; Conference: ASHRAE annual meeting, Portland, OR, USA, 22 Jun 1986
• Country of Publication: United States
• Language: English

Related Subjects

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATION
RESIDENTIAL BUILDINGS
WATER HEATING
WATER
CORROSIVE EFFECTS
WATER HEATERS
SCALING
WATER TREATMENT
ANODES
DESIGN
EFFICIENCY
ELECTRIC APPLIANCES
GAS APPLIANCES
ILLINOIS
MINNESOTA
NEW MEXICO
OHIO
SCALE CONTROL
URBAN AREAS
APPLIANCES
BUILDINGS
CONTROL
ELECTRODES
FEDERAL REGION V
FEDERAL REGION VI
HEATERS
HEATING
HYDROGEN COMPOUNDS
NORTH AMERICA
OXYGEN COMPOUNDS
USA
320106* - Energy Conservation
Consumption
& Utilization- Building Equipment- (1987-)