B344-21-880 Issue N
Page 46 © Edwards Limited 2007. All rights reserved.
Edwards and the Edwards logo are trademarks of Edwards Limited.
Maintenance
5.9 Check the heater securing nuts
If the pump is regularly heated up and cooled down, check the tightness of the heater securing nut(s) frequently.
Refer to Section 5.8 to tighten these nuts.
5.10 Clean the cooling-coil
The cooling-coil should be cleaned at least once a year, and more regularly if the water supply has a high calcium
content.
To clean the cooling-coil, flush with a suitable descaler. For example, use a 15% hydrochloric acid solution for
decalcification, then use a 5% sodium carbonate solution for neutralization.
5.11 Adjust or replace the position indicators
5.11.1 Adjust the position indicators
If the position indicators are loose, use the following procedure to adjust them.
1. Refer to Figure 27. Loosen the clamp screw (7) on the valve closed position indicator (1).
2. Slide the position indicator in the dovetail groove (3) until the gap (2) between the position indicator and the
valve actuator is correct.
3. Apply a suitable thread sealant (such as Loctite 222e) to the clamp screw (7) and tighten the clamp screw to a
torque of 0.4 Nm.
4. Repeat Steps 1 to 3 above to adjust the gap (5) between the valve open position indicator (6) and the end of the
pneumatic actuator.
5.11.2 Replace the position indicators
If the position indicators are damaged, you must replace them; refer to Section 7.2 for the Item Numbers of the
position indicator spares kits. Use the following procedure to replace the position sensors.
1. Refer to Figure 27. Loosen the clamp screw (7) on the valve open position indicator (6).
2. Slide the position indicator down the dovetail groove (3) and out of the cylinder.
3. Loosen the clamp screw (7) on the valve closed position indicator (1).
4. Slide the position indicator down the dovetail groove (3) and out of the cylinder.
5. Ensure that the dovetail groove is clean, then slide the new valve closed position indicator (1) into the dovetail
groove (3); ensure that the position indicator is oriented correctly, as shown in Figure 27.
6. Adjust the position indicator until the gap (2) between the position indicator and the valve actuator is correct.
7. Apply a suitable thread sealant (such as Loctite 222e) to the clamp screw (7) and tighten the clamp screw to a
torque of 0.4 Nm.
8. Slide the new valve open position indicator (6) into the dovetail groove; ensure that the position indicator is
oriented correctly, as shown in Figure 27.
9. Adjust the position indicator until the gap (5) between the position indicator and the end of the pneumatic
actuator is correct.
10. Apply a suitable thread sealant (such as Loctite 222e) to the clamp screw (7) and tighten the clamp screw to a
torque of 0.4 Nm.
To Next Page
Loading...
