RESIDENTIAL GAS AND ELECTRIC WATER HEATER
SERVICE HANDBOOK
Residential Electric – continued
A-7 – continued
Grounded Element Test – Amperage Method – Using “clamp type” Amperage
Meter. Many multimeters could be used to conduct this test but be certain that the
thermostat is satisfied or the amperage limits of the multimeter may be exceeded.
Complaint: A grounded element is suspected whenever the water temperature
becomes excessively hot and/or the end user must push the high limit reset to
reactivate the heater.
Amperage measures the flow of current through a wire.
Watts divided by volts = Amps
Conditions
Power on
Thermostats are satisfied
Clamp the jaws of the Amp Meter around each wire connected to an element –
one wire at a time.
If … … then
meter reads the proper amperage
(+5, -10%)
the thermostat is calling for heat
meter reads approximately ½ of the
proper amperage
replace the element
meter reads NO amperage thermostat and element are not grounded
-
Note: Amperage will only be indicated while electricity flows through a wire.
A.O. Smith Water Products Company Technical Training Department
©2005 Ashland City, TN
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