RESIDENTIAL GAS AND ELECTRIC WATER HEATER
SERVICE HANDBOOK
A.O. Smith Water Products Company
Training Department
©
2002
Ashland City, Tennessee
35
Residential Electric – continued
A-6 Circuit Servicing
Testing
A-6
-
two element, two thermostat, one high limit, two wire circuit type water
heaters.
Wired non-simultaneously – When the upper element satisfies, power switches to the
lower thermostat and element.
Element Test
OHMS Resistance Check
**
Test Conditions:
This test uses the multimeter's battery as the electrical
supply.
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.
Test probe on each terminal of an element
See OHMS Resistance Table – Page 45
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.
Element
