THE ONLY REQUIRED MAINTENANCE IS A SIMPLE THREE MINUTE CLEANING ! IT IS REQUIRED THAT UNIT BE CLEANED EVERY TWO WEEKS IF USING BATCH SODIUM HYPOCHLORITE (BLEACH). AND ONCE A MONTH IF USING CONTINUOUS PROCESSED SODIUM HYPOCHLORITE (BLEACH). TO CLEAN THE UNIT 1. SET CONTROLLER TO FEED MODE. 2. CLOSE CHLORINE SHUT-OFF VALVE. 3. INSERT CLEAN-OUT LABCOCK FLEX TUBE IN ONE GALLON OF CLEAN WATER AND OPEN LABCOCK. ALLOW ENTIRE GALLON OF WATER TO FLOW THROUGH UNIT, RINSING UNIT FREE OF BLEACH. 4. INSERT CLEAN-OUT LABCOCK TUBE IN GALLON SOLUTION OF 50% (WATER) , 50% (MURIATIC ACID 20% BAUME) AND ALLOW ACID MIXTURE TO FLOW THROUGH UNIT FOR APPROXIMATELY 10 SECONDS. 5. WITH CLEAN-OUT LABCOCK VALVE STILL OPEN, RE-INSERT LABCOCK FLEX TUBE IN FRESH GALLON OF WATER, ALLOW ENTIRE GALLON TO FLOW THROUGH THE UNIT, RINSING UNIT FREE OF MURIATIC ACID RESIDUE. 6. CLEAN Y-STRAINER IF NECESSARY. 7. CLOSE CLEAN-OUT LABCOCK VALVE. 8. RE-OPEN CHLORINE SHUT-OFF VALVE. 9. RESET CONTROLLER NOTE: THESE COMPLETE CLEANING INSTRUCTIONS ARE ALSO LOCATED ON THE FACE OF EACH UNIT. NO MORE METERING PUMPS NO MORE PROBLEMS !!!