Daily Maintenance; Weekly Maintenance - Speedaire 20 HP Manual De Instrucciones De Operación Y Piezas

Speedaire Operating Instructions & Parts Manual
Speedaire
Air Compressor
Operation (Continued)
IMPORTANT: This compressor has a
maximum operating pressure of
175 PSIG. Do not alter pressure
settings on control components
above this limit.
CONSTANT SPEED UNLOADING &
E
PILOT VALVE
N
G
This compressor is equipped with
L
head valve unloaders. The pilot
I
valve is designed to act as an
S
automatic ON and OFF air switch.
H
When in the ON position it allows
air to flow from the tank through
the valve to the compressor head
unloader mechanism, thus
actuating it. In the OFF position this
valve stops the flow of air through
the valve and releases the pressure
in the line to the head unloader.
The pilot valve works as follows:
Tank air pressure acts on the bottom
of the valve. When pressure is great
enough to overcome spring force
holding valve down on lower seat,
it lifts off seat and allows air to flow
around valve and out through side
opening in pilot valve. When valve
lifts off lower seat it moves up and
seats on upper seat where it is held
by tank pressure. When pressure in
tank and on valve drops, spring
forces valve back down on lower
seat. Air in line to device being
actuated can then escape through
upper seat and out vent hole. The
pressure at which the pilot valve is
ON or OFF is controlled by the spring
which has been installed at the
factory. A small adjustment can be
made in the field by changing the
spring force by compressing the
spring more or less with the adjusting
screw provided on the pilot valve.
COMPRESSOR PILOT VALVE
PRESSURE ADJUSTMENT
Refer to Figure 3.
Proceed with the following
instructions while compressor is
running:
1. Loosen locknut (Ref. No. 4) and
back off several turns. Do not
®
20, 25 & 30 HP Two-Stage
turn differential adjuster
(Ref. No. 3).
2. Check reading on the tank
pressure gauge. Set the
compressor maximum pressure
at 170 PSIG. Turn threaded cap
(Ref. No. 1) clockwise to
increase pressure or
counterclockwise to decrease
differential pressure.
3. After pressure is set, tighten
locknut (Ref. No. 2). Be careful
not to move threaded cap
(Ref. No. 1).
COMPRESSOR PILOT VALVE
DIFFERENTIAL PRESSURE
ADJUSTMENT
Proceed with the following
instructions while compressor is
running:
1. Loosen locknut (Ref. No. 2) and
back off several turns.
2. Check reading on the tank
pressure gauge. Set the pressure
to 30 PSIG differential (unload at
170 PSIG reload at 140 PSIG).
Turn nut (Ref. No. 3) clockwise
to increase differential pressure
or counterclockwise to decrease
differential pressure.
3. After pressure is set, tighten
locknut (Ref. No. 2). Be careful
not to move nut (Ref. No. 3).
Pilot Valve
Assembly Part No.
M2855
M2854
M2853
B-980-B
(Ref. Drawing)
Figure 3 – Adjusting Pilot Valves
Maintenance
To obtain reliable and satisfactory
service, this unit requires a consistent
preventive maintenance schedule.
A maintenance schedule form is
included to aid in keeping the proper
records.
any maintenance function, switch
main disconnect switch to OFF
position to assure no power is
entering unit. Lock out or tag out all
sources of power. Be sure all air
pressure in unit is relieved. Failure to
do this may result in injury or
equipment damage.

DAILY MAINTENANCE

1. Check oil level of both compressor
2. Drain moisture from tank by
valve if tank pressure exceeds 25 PSIG.
3. Turn off compressor at the end of

WEEKLY MAINTENANCE

1. Clean dust and foreign matter
2. Remove and clean intake air filters.
Pressure Range
75 - 95 PSIG
90 – 120
PSIG nozzle pressure when cleaning
140 - 170
element parts with compressed air. Do
not direct compressed air against
human skin. Serious injury could
result. Never wash elements in fuel
oil, gasoline or flammable solvent.
3. Check V-belts for tightness.
a. Remove bolts and guard to access
b. Loosen mounting hardware which
4
3Z411A
Before performing
and engine if so equipped. Add
quality lubricating oil as required.
See section on "Compressor Oil
Specifications".
opening tank drain cock located in
bottom of tank. Do not open drain
each day's operation. Turn off
power supply at wall switch.
from cylinder head, motor, fan
blade, air lines, intercooler and
tank.
Do not exceed 15
The V-belts must be tight enough
to transmit the necessary power to
the compressor. Adjust the V-belts
as follows:
compressor drive.
secures motor to base. Slide motor
within slots of baseplate to desired
position.