Pentair AUTOTROL 740 Service Manual Download

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To remove microswitch:
1.  Disconnect power to the switch.
2.  Remove cover.
3.  Remove controller.
4.  Unscrew switch from top plate.
5.  Disconnect wires.
To install microswitch:
1.  Connect wires.
2.  Screw switch base to top plate using the switch guide pin

over screw boss.

3. Attach the switch cam to front of the camshaft with a self-

tapping screw. Adjust to the appropriate cycle and tighten.

NOTE:

The cam for this switch is adjustable. To have the

microswitch activate at a different point in the cycle,

rotate the cam as needed. To rotate the cam loosen

the center screw, tighten when the cam is in the

new position.

Spring (Valve Discs)

This spring is a one-piece metal spring that applies pressure

to the valve discs holding them closed. The rotating camshaft

overcomes this pressure to open the valve discs as needed.

The shape of the spring is critical for proper operation.

WARNING:

Do not attempt to straighten or repair this

spring. If this spring is damaged, valve discs

may not operate correctly.

To remove spring:

Push open

Valve Discs

Spring locked under tabs

1.  Disconnect power to the unit.
2.  Remove cover.
3.  Remove motor.
4.  Remove camshaft.
5.  Place unit in bypass.
6.  Release water pressure by pushing the last valve discs

open with a screw driver.

7. Locate valve discs 2, 3 and 4 for 255 valve or valve discs 3, 4

and 5 for Performa valves.

8. Position yourself on the spring side of the valve discs.
9. Place two (or more) fingers on the flat part of the spring.
10. Move the fingers toward the valve discs and into the spring

valley between the previously located valve discs.

11. By pulling back and up on the spring, the spring will pop

out of the valley.

12. Pull back further to remove the spring.

To install spring:

1. Inspect the spring for damage. Do not attempt to repair a

bent spring.

2. Position yourself on the spring side of the valve discs.
3. Position the spring over the valve body close to final

position. The wide spring segments will be located at the

wide valve discs. The curve of the spring will be down into

the valley.

4. The long flat close edge is inserted first. This edge slides

into a channel on the valve body.

5.  Rock the spring back and place the flat edge into the channel.
6.  Lower the springs until they rest on top of the valve discs.
7.  A tool (phillips screwdriver) will be needed to push the

springs in place.

8. The spring posts will guide the spring into position.
9. Hold the flat part down with one hand.
10. Spread your fingers apart to cover the length and push down.
11. With the other hand use the tool to push down in the valley

of each spring segment.

The spring will slide off the top of the valve disc downward.

The small projection on the end of the spring will drop into the

hole in the valve disc to provide secure positioning. Repeat for

all spring segments.

NOTE:

If a spring segment goes beyond the locating hole, it can

be pulled back using a small flat blade screwdriver.

NOTE:

In high pressure (80 psi and higher) applications, the

standard single valve disc springs can be installed on

top of the one piece spring.