Jandy AquaPure Cell Replacement: End-of-Life Signs and Procedure

When to Replace the Cell

The electrolytic cell is a consumable component. The bipolar electrode plates have a specialized coating that enables electrolysis. Over time, this coating gradually wears through normal use. When the coating is depleted, the cell can no longer sustain adequate current flow for chlorine production.

Definitive end-of-life indicators

• Service codes 120, 121, or 123 persist after acid washing the cell AND confirming salt is at 3.0-3.5 gpl AND water temperature is above 60°F AND the DC cord connections are clean and tight.
• Acid wash produces no foaming (cell is clean) but low current codes continue.
• If recurring low-current codes persist after thorough cleaning, the cell has likely reached end of life and should be replaced.
• Chlorine production cannot maintain 1-3 ppm even at 100% output with adequate pump run time.
• Level 2 code 194 (cell current 85% lower than desired with cell voltage above 19V) generates code 125 as a secondary indicator.

Factors that affect cell lifespan

• Pool size vs. cell capacity: An undersized cell (700 model on a 30,000+ gallon pool) runs at higher output and wears faster.
• Daily run hours: More hours per day means more electrolysis cycles and faster plate erosion.
• Production percentage: Running at 100% constantly gives the cell no rest. Running at 90% provides 10% rest time that extends life.
• Water chemistry: Low salt (<2.5 gpl) accelerates erosion. High calcium causes scaling that forces more acid washes, which also erode the coating.
• Cold water operation: Running the cell in extremely cold water contributes to reduced operating life.

Cell Replacement Procedure

Replacing an existing 3-port cell

1. Turn off the pool pump.
2. Unplug the DC cable from the existing cell.
3. Disconnect the DC cord from the wiring harness inside the power center. Loosen the strain relief fitting.
4. Remove the flow/temp/salinity sensor from the cell by unscrewing the coupling nut on the sensor port. Pull straight out.
5. Remove the old cell body by unscrewing the coupling nuts on the flow ports.
6. Replace existing union O-rings with the new O-rings provided in the cell kit.
7. Install the new cell and tighten coupling nuts.
8. Install the flow/temp/salinity sensor into the available sensor port on the new cell.
9. Plug the new DC cord (provided with the cell kit) into the cell stud terminals in either direction. Ensure the plug is fully seated.
10. Feed the DC cord through the strain relief fitting and connect to the spade connectors on the wiring harness inside the power center.
11. Tighten the strain relief. Leave a little slack for the cables inside the enclosure.
12. Verify all connections: sensor plugged in, DC cord plugged in, AC wiring correct.
13. Turn on the pump and the power center. The unit will display "Wait" during the 6-minute calibration cycle.
14. Verify salinity, temperature, and flow readings are normal. Set the chlorine production rate.

Extending the Life of Your New Cell

• Maintain salt at 3.0-3.5 gpl. Never operate below 2.0 gpl.
• Keep pH at 7.4-7.6 and calcium hardness at 175-400 ppm to minimize scaling.
• Use stabilizer (CYA) at 50-75 ppm to protect chlorine from UV, reducing the workload on the cell.
• Run at 90% or less when possible to give the cell rest periods.
• Avoid unnecessary acid washing. Only clean when scale is actually present.
• Do not add chemicals or salt through the skimmer.