Leslie Controls Temperature Fixed and Adjustable Proportional band type - Manual (Page 8)

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7. Loosen lever adjusting screw lock nut and screw
adjusting screw into lever toward plunger plug if
dimension is less than 11/32”. Replace lever and
fulcrum pin. Hold lever tip down so that adjusting
screw rests firmly against end of plunger plug. Check
clearance. Repeat procedure until a clearance of
11/32” is obtained. Hold adjusting screw in place with
a screwdriver and tighten lock nut.
8.
Replace lever, fulcrum pin and retaining washer, lever
spring and lever spring screw. Tighten lever spring
screw. Replace cover and cover screw.
9.
Adjust pilot for required control temperature. Replace
temperature adjusting knob with pointer in center
position of cover and tighten adjusting knob lock
screw.
ADJUSTING PROPORTIONAL BAND
MECHANISM
NOTE: This adjustment is factory set with and air supply
pressure of 20 psig. Adjustment should not be disturbed
unless replacement of a part is necessary in the
proportional band mechanism or if the inlet supply
pressure is changed to a higher value. If it is necessary to
disturb adjustment, readjust in the following manner.
1.
Loosen set screw in knob (39). Remove knob from
proportional band screw (23).
2.
Supply desired operating pressure to temperature
pilot. Then turn proportional band screw (23) inward
toward seat until all air flow ceases through pilot. (Do
Not squeeze screw against seat.)
3.
Back proportional band screw (23) away from its seat
the number of degrees shown in curve Figure 9 for the
particular supply pressure in use.
4.
Replace knob (39) on proportional band screw (23)
with pointer against ping in plug (24) in a fully
clockwise position.
5.
This setting will produce minimum proportional band.
Turning knob (39) counter-clockwise, widens
proportional band. Maximum width of band is reached
when pointer is turned counter-clockwise the percent
of full rotation shown in curve Figure 10 for the
particular air supply pressure in use.
6.
Adjust for desired temperature and width of band as
described under “Operation”.
Figure 6 - Location of Minimum Band Setting
Figure 7 - Location of Maximum Band Setting