RESIDENTIAL GAS AND ELECTRIC WATER HEATER
SERVICE HANDBOOK
Residential Electric – continued Cold tank of water • Single Electrical Service • Single Phase
Power Enters
Terminal 1 Of Upper
High Limit And Terminal
3 Of Upper Thermostat
Upper High Limit 1, 2 Is Closed
Upper Thermostat 3, 4 Is Open
Upper Thermostat 1, 2 Is Closed
Upper Element Is On
No Power
To Lower
High Limit
Term 1 To
p
1/3 Of Tank Is Heated
Upper Thermostat 1, 2 Opens,
3, 4 Closes
Power From Upper Thermostat 1
To Lower High Limit 1.
Lower High Limit
1, 2 Is Closed
Lower Thermostat 1
,
2 Is Closed
Lower Element Heats Bottom 2/3 Of Tank
Upper High Limit 3, 4
Is Closed
Lower High Limit 3, 4
Is Closed
Terminal 3 Of Upper
High Limit And Term 3
Of Lower High Limit
Fused Disconnect
A-7 Circuit Prior to 1996
A.O. Smith Water Products Company Technical Training Department
©2005 Ashland City, TN
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