Service

Service

Before Servicing

NOTICE

To avoid damaging circuit board when servicing, wear Part No. 112190 grounding strap on wrist and ground appropriately.

1.Flush system and follow Pressure Relief Proce- dure in your ProMix Repair-Parts manual.

2.Close main air shutoff valve on air supply line and on ProMix.

3.Shut off power (0 position). FIG. 3.

4.Shut off power at main circuit breaker.

0 = OFF

TI12657a

FIG. 3: Power Off

5.Disconnect all air and fluid lines from the flow con- trol module.

6.Model 24H989 only: Disconnect all fluid lines from the pressure sensor fitting (626).

7.Disconnect the flow control cable from the flow con- trol harness (624). FIG. 4 or FIG. 5.

After Servicing

After servicing, be sure to follow the Start Up checklist and procedure in the ProMix Operation manual.

Servicing the Regulator and Pressure Sensor (Model 249849 only)

Regulator Service Kit 15G843 is available. Kit parts are marked with an asterisk, for example (602*). For best results, use all parts in the kit.

Sensor Service Kit 15G867 is available to service the pressure sensor only. Kit parts are marked with a sym- bol, for example (602‡). For best results, use all parts in the kit.

1.Follow Before Servicing, above.

2.Remove the four screws (605) and the nut (601) from the underside of the air plate (607). Separate the air plate and fluid plate. FIG. 4.

3.Unscrew the pressure sensor (620) from the fluid plate (606).

NOTE: If you are only replacing the pressure sensor kit 15G867, skip to step 6.

4.Remove the plug (615) and o-ring (604) from the top of the fluid plate (606). Remove the parts of the dia- phragm assembly (613, 610, 609, 612, 617, 616).

Remove and discard the dowels (623).

5.Reassemble the diaphragm assembly using the new parts from the kit. Be sure the AIR SIDE of the dia- phragm (617) faces down. Torque the nut (601) to 8-10 in-lb (0.9-1.1 N•m).

6.Install a new o-ring (602) on the pressure sensor (620) and screw the sensor into the fluid plate (606).

7.Reinstall the fluid plate on the air plate. Be careful not to pinch the pressure sensor cable. Torque the screws (605) to 30-40 in-lb (3.4-4.5 N•m).

8.Reconnect the three cables to J1, J2, and J4 on the circuit board (618). FIG. 6.

9.Reattach the air plate (607) to the housing (611). Torque the screws (605) to 30-40 in-lb (3.4-4.5 N•m).

10.Reattach the flow control cable and all air and fluid lines.

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3A2097B

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Graco 3A2097B important safety instructions Service, Follow Before Servicing, above