Control System Adjustment - Sullair 20/12 Series Operator's Manual And Parts List

Section 6
MAINTENANCE
Figure 6-4 Main Fluid Filter (P/N 045111)
* Seal Repair Kit P/N 001132
** Element Repair Kit P/N 001094
7. Carefully push the upper element back into the
position on the filter head. The element will pro-
trude from the bottom of the head (approximately
5") when properly seated.
8. Carefully push the lower element into position un-
der the upper element.
9. Hold the canister in position under the housing and
replace the capscrews, securing the canister and
filter head.

CONTROL SYSTEM ADJUSTMENT

Ref er t o F igur es 6 -- 5
Control System, it is necessary to determine the de-
sired operating pressure range and also the maxi-
mum pressure at which your compressor is to oper-
ate. The pressure must not exceed the maximum op-
erating pressure which is stamped on the compres-
sor serial number nameplate. The following explana-
tion applies to a typical installation with a desired op-
erating range of 250 to 260 PSIG (1724 to 1793kPa).
This information will apply to a compressor with any
other operating range except for the stated pres-
sures.
With the shut--off valve closed (or slightly cracked
open) start the compressor. Observe the line pres-
sure gauge and pressure switch contacts. When the
line pressure reaches the desired pressure, the pres-
24
and 6 -- 6. P r ior t o adjus t ing t he
sure switch contacts should open. If the pressure
switch contacts do not open or they open prior to the
des ir ed pr es s ur e, t he pr es s ur e s wit c h s et t ing will r e-
quir e adjus t m ent ( r ef er t o F igur e
FOR PRESSURE RANGE ADJUSTMENT:
1. Remove cover to pressure switch.
2. Turn the range adjusting screw to the high pres-
sure setting. Turning the screw counterclockwise
lowers both the high and low pressure equally.
FOR DIFFERENTIAL ADJUSTMENT:
Differential is the difference between the high and
low pressure settings (10 PSIG [7kPa]) typical.
Turn the differential adjusting screw to the lower (re-
set) setting. Turning the screw counterclockwise wid-
ens the differential by lowering the reset (lower) set-
ting only.
When the pressure switch adjustment is complete,
the pressure regulator should be adjusted for the
pressure at which modulation of air delivery should
begin. In this case, that pressure will be 250 PSIG
(1724kPa). The regulator is adjusted by loosening
the jam nut on the end of the cone shaped cover of
the pilot pressure regulator (refer to Figure 6--7 for
the location). When the jam nut loosened, turn the
adjusting screw clockwise to increase or counter-
clockwise to decrease the setting.
Once the pressure rises above 260 PSIG (1793kPa),
a factory set pilot valve opens allowing pressure to
flow into the Sullicon Control. At this time the Sullicon
Control should be full stroked.
Figure 6-5 Pressure Switch (P/N 245753)
6 -- 5) .