Salt Cell Cleaning & Maintenance

Goal

Clean and inspect a salt chlorine generator (SWG) cell to maintain chlorine production and extend cell life. Salt cells calcify in hard-water pools - calcium scale on the titanium plates blocks the electrolysis process; chlorine production drops gradually until the pool is undersanitized. Annual cleaning prevents 80 % of "salt system not making chlorine" calls.

Prerequisites

• Acid wash solution: 1 part muriatic acid to 4 parts water (for cleaning calcium scale)
• Bucket or PVC tube + caps for soaking the cell
• Rubber gloves + eye protection (acid is corrosive)
• Hose for rinsing
• Replacement o-rings if existing show wear
• 30 - 60 minutes

Steps

1. Cut power to the SWG control box. The cell is energized at low voltage but high current; never service while powered.
2. Close return valves OR shut down pump. Whichever closes off the cell from pool flow.
3. Disconnect cell. Unscrew the unions on each side; let drain into a bucket.
4. Visual inspection. Look at the plates:

• Clean, gray titanium with even coating → cell is healthy + may not need acid wash
• White flaky calcium scale → standard maintenance acid wash
• Heavy scale that doesn't rinse → soak in acid solution
• Erosion of the plate coating + visible bare titanium → cell at end-of-life; replace

1. Rinse cell with hose to remove any loose debris. If this clears the plates, you're done; reinstall.
2. For calcified cells: mix acid solution in a non-metal bucket OR use a dedicated cell-cleaning PVC tube. Submerge the cell vertically (don't fill - too much acid wastes; just submerge plates).
3. Soak 10 - 15 minutes. Calcium dissolves visibly; you'll see bubbles + the solution turn cloudy.
4. Inspect. If plates are clean, proceed to step 9. If scale remains, dump solution + mix fresh acid; re-soak. Don't extend a single soak beyond 30 minutes - it damages the coating.
5. Rinse thoroughly with fresh water - minimum 60 seconds of hose flow on each side. Residual acid going back into the pool drops pH.
6. Inspect o-rings on the unions. Replace if cracked, flat, or dry.
7. Reinstall the cell. Hand-tighten the union nuts; the o-ring does the sealing, not the torque.
8. Open valves + restore power. Watch for leaks at the unions for 5 minutes.
9. Verify operation. SWG control should report chlorine production (LED or display indicator). Test water chlorine in 24 - 48 hours to confirm normal output.

Verification

• Plates are visibly clean
• No leaks at union connections
• Control box reports normal operation
• Chlorine reading 1 - 3 ppm at 24 - 48 hour follow-up

Troubleshooting

• Cell still showing "low salt" after cleaning: cell may be at end-of-life (worn plate coating). Verify with the customer's salt-meter reading (should match the control box).
• Control reports "inspect cell" error: usually means the cell has gone open-circuit. Replace.
• Calcium returns within months: customer has hard fill water + may need to manage calcium hardness separately. Partial drain + dilution annually.
• Pool dropping pH after cleaning: residual acid in lines. Run pump for 30 minutes, retest, dose if needed.

References

• Manufacturer service literature for the specific SWG (Pentair IntelliChlor, Hayward T-Cell series, Jandy AquaPure)
• Manuall internal: Weekly Recurring Pool Service, Pool Chemistry Quick Reference