Hi-Limit Switch - A.O. Smith 240 T-H3J Service Manual

10-14. Hi-limit switch

Part#
Function
Failure events
Effects on the water heater
if hi-limit switch fails
Error codes when hi-limit
switch fails
Diagnostic
Color / Number of wires
When detecting temperature of the hi-limit switch exceeds the activation temperature
Deactivation: to reset switch back to ON mode, press the reset button
540 (T-H3) models
240 (T-H3J), 340 (T-H3S) and 540 (T-H3) models Service Manial
240 (T-H3J) /340 (T-H3S) models
540 (T-H3) models
valves are severed, shutting down the water heater instantly. The "111" or
"121" error codes will display.
1.
process, and either the "111" or "121" error code will display.
111
The water heaters don't have the "141" error code that was used in our
previous models. This error code is now replaced by the "111" and the
"121" error codes.
Blue-Blue
Reset Button
Reset Button
38
Page
Unit Part#
Checkpoint
1-1/4" (33 mm) 5/8" (15 mm)
1-1/4" (31 mm) 5/8" (16 mm)
CONFIDENTIAL
Ver. 1.00
#412
121
C1
"85" mark