Graco President 24H627, Instructions-Parts List Manual

Page: 8 / 20

Operation
8 3A1450B
Operation
Pressure Relief Procedure
1. Close the bleed-type master air valve (M).
2. Open the dispensing valve, if used.
3. Open all fluid drain valves (N) in the system, having
a waste container ready to catch drainage. Leave
drain valve(s) open until you are ready to pump
again.
Prime the Pump
1. Fill the TSL reservoir to the Maximum fill line with
Throat Seal Liquid (TSL). See F
IG
. 3 on page 10.
NOTE: During operation the TSL level in the reservoir
will fluctuate slightly at pump changeover.
2. Close pump air regulator (L) by turning knob coun-
terclockwise reducing pressure to zero. Close
bleed-type air valve (M). Also verify that all drain
valves (N) are closed.
3. Connect air line (J) to bleed type air valve (M).
4. Check that all fittings throughout system are tight-
ened securely.
5. Connect the fluid supply line (C) from the mix tank
shutoff valve (D) to the pump.
6. Connect the fluid line (E) to the pump outlet.
7. Open bleed-type air valve (M). Slowly turn pump air
regulator (L) clockwise, increasing pressure until
pump starts.
8. Cycle pump slowly until all air is pushed out and
pump and hoses are fully primed.
9. Verify that pump actuations are priming the pump
wet-cup. If not, confirm that the TSL pump piston is
being depressed at bottom changeover, and that
reservoir check valves are not stuck closed.
10. Close the fluid shutoff valve (D) downstream of the
pump. The pump should stall against pressure.
NOTE: In a circulation system, the pump operates con-
tinuously until the power supply is shut off. In a
direct-supply system, the pump starts when the dis-
pense valve is opened, and stops when the dispense
valve is closed.
Stop the Pump at the Bottom of
Its Stroke
Relieve the pressure when you stop the pump for any
reason. Stop the pump on the downstroke, before the air
motor changes over.
Shutdown
Follow Pressure Relief Procedure, page 8.
Always flush the pump before the fluid dries on the dis-
placement rod. See Flushing on page 9.
NOTICE
Failure to stop the pump at the bottom of its stroke
allows fluid to dry on the piston rod, which can dam-
age the throat packings and the TSL pump piston seal
when the pump is restarted.