Rola-Chem Pro Series 300 Replacement Timer (543846)

Restore the timing function of a compatible Rola-Chem Pro Series 300 chemical-feed controller with this replacement timer. The timer is a service component for the Pro Series 300 equipment family, rather than a complete chemical feeder, pump, or replacement control cabinet.

How This Component Fits the System

In a high-rate sand filter, incoming water is distributed across the sand bed, suspended particles are trapped by the filtration media, and filtered water is collected by the internal underdrain and returned to the pool. Internal diffusers, laterals, standpipes, and air-relief plumbing each perform a different role. Hayward explains this water path in its ProSeries service literature; replacing the correct internal component matters to efficient operation and avoiding unwanted sand migration.

Timing is part of the way automated feed equipment is operated, so selecting the correct replacement matters. Before service, compare the part number and timer configuration with the existing unit and review the controller documentation for the required connections. This listing identifies the replacement timer itself; it does not establish that unrelated electrical or feed components are included.

Replacement and Maintenance Considerations

A well-planned repair includes inspecting the condition of the neighboring assembly before reinstalling the replacement. Look for worn mating surfaces, loose retainers, damaged connections, corrosion, or other conditions relevant to the component being serviced. Recommission the system using the manufacturer procedure rather than assuming that installing a new part alone resolves the original operating problem.

For this particular listing, the ordering reference is 543846. The identifying description is Rola-Chem Pro Series 300 Replacement Timer (543846). Matching the original unit and the manufacturer parts illustration is particularly important where closely related models have different mounting or electrical requirements.

Practical Features and Service Benefits

• Maintains the intended water path through the sand-filtration assembly.
• A correctly installed internal component helps prevent bypass or unwanted disturbance of filter media.
• Inspecting the sand bed while the filter is opened can reveal broken parts or misplaced media.
• Production-date revisions should be checked against the tank label and relevant service diagram.
• Depressurize, isolate, and drain the filter before opening or servicing any pressurized component.
• Replacing the affected subassembly can avoid unnecessary replacement of a serviceable filter tank.