A.O. Smith TC-049R3 Service Handbook page 28

RESIDENTIAL GAS AND ELECTRIC WATER HEATER
Residential Electric – continued
Surface Mounted Thermostat (s) and High Limit (s)
The thermostats and high limits are held against the side of the tank. As the tank surface heats or
cools, a metal disc inside of the control expands or contracts to open or close electrical contacts
in the controls.
They will satisfy within 10°F of setting. The tank surface has to cool 8 - 15°F to reactivate these
controls.
Model Circuit
2
A-6, A-7
59T-Style 4100
2
A-6, A-7,
59T-Style 4000
3
89T33
3
C-2, A-7
89T13
2
59T-Style 4000
2
AW-Style 7135
4
A-6, A-7,
66T-Style 4400
3
A-6, A-7,
89T
1
"
Older" = series 916 or older.
"Newer" = series 917 or more current – (Began approximately January, 1996)
2
Older 59T controls had a maximum setting of 170°F. Replacement 59T controls will stop at
150°F.
3
89T controls are combination High Limit/Thermostat, one piece controls.
4
66T limits may be mounted onto 59T thermostats.
66T4400
59T4100
A.O. Smith Water Products Company
©2005
SERVICE HANDBOOK
Older Models
X A-6
X
C-2
A-6
A-6
A-7 X
X
C-2
C-2
Thermostat
59T4100
Newer
1
Models Location
Upper Tank
X Lower Tank
X Upper Tank
X Lower Tank
X Lower Tank
X Upper Tank
X Lower Tank
X
89T33
Technical Training Department
27
Temperature
Range °F
110-170
110-170
90-150
90-150
90-150
110-170
190°
170°
89T13
Combination High Limit &
Thermostat
Ashland City, TN