RESIDENTIAL GAS AND ELECTRIC WATER HEATER
SERVICE HANDBOOK
A.O. Smith Water Products Company
Training Department
©
2002
Ashland City, Tennessee
26
Residential Electric – continued
Cold tank of water
•
Single Electrical Service
•
Single
Phase
A-7 Circuit
Prior to 1996
Fused Disconnect
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
Top 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
Terminal 3 Of Upper
High Limit And Term 3
Of Lower High Limit
Upper High Limit 3, 4
Is Closed
Lower High Limit 3, 4
Is Closed
Lower Element Heats Bottom 2/3 Of Tank
