What Does This Error Mean?

A Hayward chlorine feeder that stops dispensing is usually clogged with calcium scale from dissolved trichlor tablets. Close the bypass valve, empty the feeder, and soak the body in a diluted muriatic acid solution to dissolve scale. Always use slow-dissolving 3-inch trichlor tablets — smaller pucks and shock tablets dissolve too fast and cause faster clogging.

Affected Models

Hayward CL200
Hayward CL220
Hayward CL110
Hayward CCH Series In-Line Feeders
Hayward Off-Line Chlorine Feeders

Common Causes

Calcium scale buildup from dissolved trichlor tablets blocking the outlet tube or metering valve
Wrong tablet type — shock, di-chlor, or unstabilised tabs dissolve too fast
Feeder valve set to 0 — no flow through the unit
Float clogged with scale preventing it from rising with water level
Feeder body cracked, allowing bypass of the metering valve

How to Fix It

Close the bypass valve and empty the feeder.

Turn the feeder bypass valve to the off position to stop flow through the feeder. Open the feeder lid and remove any remaining tablets. Dispose of old tablet residue carefully — it is still acidic and chemically active.
Soak in a diluted acid solution.

Mix one part muriatic acid with ten parts water in a plastic bucket (always add acid to water, never water to acid). Place the feeder body and internal parts in the solution for 15–30 minutes. The scale will fizz and dissolve. Rinse thoroughly with clean water before reassembly.
Clear the outlet tube.

After soaking, use a small brush or pipe cleaner to clear the outlet tube and metering valve port. These narrow passages clog first and restrict even after the body is clean. Confirm water flows freely through the outlet before reloading tablets.
Set the feeder valve correctly.

The metering valve on the side of the feeder controls how much water flows through the tablet chamber. For a residential pool, set it between 1 and 3 — a setting of 0 means no water passes through and no chlorine is dispensed. Adjust based on your pool's daily chlorine demand.
Use only 3-inch trichlor tablets.

Hayward in-line and off-line feeders are designed for 3-inch slow-dissolving trichlor tablets. Di-chlor granules, shock, calcium hypochlorite, or 1-inch tabs dissolve much faster, creating concentrated residue that accelerates scale and clogging. Never mix tablet types in the feeder.

When to Call a Professional

If descaling does not restore flow and the feeder body is not cracked, the internal metering valve or float assembly may need replacement — contact your pool supply dealer.