Prime Empty System

Recirculate Prior to Spraying or Re-Prime After a Pump Runs Dry

NOTE: Agitate, recirculate, and heat the material only as necessary to avoid mixing air into the fluid.

Use the recirculation mode when heating the material is required. Note the temperature at the top of the heater (outgoing or back to the hopper). When the thermome- ter reaches operating temperature, the material is ready to spray.

If using a system that does not require heat, recircula- tion is still required prior to spraying. Recirculation ensures that any settled fillers are mixed in, the pump lines are fully primed, and the pump check valves are operating smoothly.

Recirculation also allows you to re-prime one side that has run dry.

1.Follow Prime Empty System, page 23.

2.Close the dual shutoff handle (AE).

AC

AE

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3.Ensure the recirculation hoses (U) are in the correct hoppers (J).

U

J

4. Open the circulation valve handle (AC).

5.Turn down the air pressure regulator (CB) and then open the main air shutoff valve (CA). Use the air pressure regulator to slowly increase the air pres- sure to the pumps until they start running slowly.

CB

CA

6.Run the pumps for a few minutes or until the mate- rial has reached the desired temperature. See Heat Fluid.

7.Close the main air shutoff valve (CA).

CA

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8. See Spray, page 26.

Heat Fluid

To heat fluid evenly throughout the system:

1.Circulate the fluid at approximately 1/2 gpm

(10-20 cycles/min.) to raise the temperature of the hoppers to 80-90° F (27-32° C).

2.Decrease the circulation rate to approximately

0.25 gpm (5 cycles/min.) to increase the heater out- let temperature to match the spray temperature.

NOTE: Circulating the fluid too quickly without decreasing the circulation rate will increase only the hopper temperature. Similarly, circulating fluid too slowly will increase only the heater outlet tempera- ture.

3A0420T

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Graco 3A0420T important safety instructions Heat Fluid, Follow Prime Empty System