RESIDENTIAL GAS AND ELECTRIC WATER HEATER
SERVICE HANDBOOK
A.O. Smith Water Products Company Training Department
©2002 Ashland City, Tennessee
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Residential Electric – continued
A-7 Voltage Check - continued
Complaint: Lack of Hot Water
Test Conditions:
Upper thermostat satisfied
Test between upper high limit 4 and upper thermostat 4
If … … then
proper voltage is not present replace upper thermostat.
proper voltage is present continue to next step.
Test between lower high limit terminal 1 and 3 or L1 and L3
If … … then
proper voltage is not present • check wiring to upper thermostat and
heater junction box.
• check that off peak meter is not
“Open”.
proper voltage is present continue to next step.
Test between lower high limit 2 and 4 or L1 and L4
If … … then
proper voltage is not present push lower high limit reset.
pushing reset restored voltage • conduct lower thermostat check
• conduct lower element checks
pushing reset did not restore voltage replace lower high limit
proper voltage is present continue to next step
