L.B. White Pilot - Manual (Page 68)

Very little actual servicing of the high-limit switch is required.
However, it is good to know the location of the switch when
working on the heater. Typically, the switch is located on the
heat chamber face or at another similar location at the
burner end of the heater. Some models may have the switch
located on a bracket near the burner.
Depending upon model, and design sequence, some heaters
used a spacer between the legs of the high limit switch and
the heat chamber. These allowed the switch to open at the
proper temperature. If your heater is so equipped, insure the
spacers are reinstalled prior to mounting the switch. Spacer
thickness may vary with model and design. Refer to
appropriate parts list.
Other heater designs may have the switch mounted directly
to the flat of the heat chamber face. Familiarize yourself with
switch mounting characteristics.
High-Limit Switch Replacement
Servicing
Instructions
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August 1999
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