Pool Chlorine Lock

Chlorine lock is a condition where high levels of cyanuric acid (CYA) reduce the effectiveness of chlorine, preventing proper sanitization.

What Causes Chlorine Lock?

  • Excessive stabilizer (CYA) levels binding to free chlorine.
  • Prolonged chlorine use without proper water dilution.
  • Incorrect water balance affecting chlorine efficiency.

How to Fix Chlorine Lock

  • Partially drain and refill the pool to reduce CYA levels.
  • Use non-stabilized chlorine sources like liquid chlorine.
  • Test and maintain proper CYA-to-chlorine ratio.

Related Terms

  • CYA (Cyanuric Acid) – A stabilizer that protects chlorine from UV degradation.
  • Free Chlorine (FC) – The active and available chlorine that sanitizes pool water.
  • Shock Treatment – The process of adding a high dose of chlorine or oxidizer to break down contaminants.

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