Winterizing Commercial Pools: A Comprehensive Shutdown Guide

Preparation Timeline

Proper winterization requires planning beginning 4-6 weeks before anticipated closure:

6 Weeks Before: - Schedule professional inspection of all equipment - Order winterizing chemicals and supplies - Book winter cover installation if applicable - Review and update closure procedures 2 Weeks Before: - Begin reducing water temperature gradually - Deep clean all pool surfaces - Shock treat and balance water chemistry - Test all equipment under actual operating conditions Final Week: - Confirm weather forecast for closure window - Notify facility users of closure dates - Schedule winterization crew - Prepare documentation for insurance/records

Water Treatment Before Closure

The water left in the pool requires specific treatment to prevent algae growth and surface staining:

Chemical Balancing: - pH: 7.2-7.6 - Total alkalinity: 80-120 ppm - Calcium hardness: 200-400 ppm - Free chlorine: 3-5 ppm (before cover) Winterizing Chemicals: - Algaecide (polyquat-based, 60%): 16 oz per 10,000 gallons - Metal sequestrant: Per manufacturer dosing - Enzyme treatment: Reduces organic load over winter Water Level: - Lower 6-12 inches below skimmer openings - Allow for precipitation without overflow - Mark water level for spring comparison (indicates leaks)

Equipment Protection Procedures

Each equipment category requires specific protection:

Pumps: 1. Close isolation valves 2. Remove drain plugs (store in pump basket) 3. Use wet/dry vac to remove residual water 3. Apply pump saver or antifreeze to volute 4. Cover with breathable tarp Filters: - Sand filters: Drain completely, leave valve in "winterize" or recirculate position - Cartridge filters: Remove and clean cartridges, store dry - DE filters: Remove grids, clean and inspect, store separately Heat Pumps: 1. Power down at disconnect (not just control panel) 2. Close water isolation valves 3. Drain heat exchanger using lowest point drains 4. Blow out with compressed air (10 PSI maximum) 5. Cover unit (manufacturer cover recommended) Salt Chlorinators: 1. Remove cell and clean with acid solution 2. Store indoors in dry location 3. Drain control unit tubing 4. Power down at breaker Automation Systems: - Download and backup configuration - Photograph all settings for reference - Remove sensitive components if unheated building - Note: Many modern systems have freeze protection mode

Spring Reopening Checklist

Systematic reopening prevents damage and ensures safe operation:

Pre-start Inspection: - [ ] Visual inspection of all equipment for damage/pest intrusion - [ ] Check electrical connections for corrosion - [ ] Verify no standing water in outdoor electrical enclosures - [ ] Confirm water level at operational height Equipment Startup: 1. Remove winter covers, clean and store 2. Reinstall any removed components (cells, cartridges) 3. Close drain valves, open isolation valves 4. Prime pumps manually (fill volute with water) 5. Start circulation system, check for leaks 6. Add initial sanitizer once filtration is operational Water Restoration: - Test and balance all parameters - Shock treat with 10 ppm free chlorine - Run filtration 24-48 hours before reopening - Vacuum and brush pool surfaces - Final water test before public access System Testing: - Verify all safety equipment functional - Test emergency shutoffs - Calibrate chemical controllers - Document startup readings for warranty/maintenance records

---

For facilities in extreme climates (Nordic regions, continental interiors), consider our professional winterization service including equipment removal and climate-controlled storage options.