A.O. Smith TC-049R3 - page 48

RESIDENTIAL GAS AND ELECTRIC WATER HEATER
SERVICE HANDBOOK
Residential Electric – continued
A-7 Service – continued
Element Test
OHMS Resistance Check**
Element
Test Conditions:
Element(s) not heating or water becoming excessively hot.
This test uses the multimeter's battery as the electrical
supply.
Procedure:
Power to the water heater is "OFF".
Multimeter set to OHMS scale testing.
Black lead "Common" port.
Red lead in "Ω" or " OHMS" port.
Dial indicator set to scale above expected indication.
Note: Volts divided by amps = OHMS
Disconnect wires from the element terminals.
See OHMS Resistance Table – Page 52
Test probe on each terminal of an element
If … … then
proper resistance (+7.5%) is present continue testing.
meter reads “0” • check OHM scale setting
• replace element.
meter reads “1” or off scale replace element.
** The above test can also be conducted with the element removed from the tank.
A.O. Smith Water Products Company Technical Training Department
©2005 Ashland City, TN
47