How To Close Above Ground Pool For Winter

Properly winterizing an above ground pool involves balancing chemistry, lowering water levels to safe skimmer thresholds, draining filtration equipment, and securing a heavy-duty winter cover. Executing these steps before freezing temperatures arrive protects your vinyl liner, prevents structural freeze damage, and ensures a crystal-clear opening next spring.

Pre-Operation & Equipment Checklist

Closing your above ground pool efficiently requires a systematic approach to gather materials and verify site conditions. Neglecting preparation risks equipment cracking or severe water contamination over the off-season.

• Essential Gear, Tools, and Materials:
  
  
  • Water test kit or strips (pH, total alkalinity, calcium hardness)
  • Winterizing chemical kit (winterizing algaecide, shock, and slow-dissolving floaters)
  • Pool brush, telescoping pole, heavy-duty leaf net, and vacuum
  • Gizzmo skimmer bottle and expansion plugs (rubber freeze plugs)
  • Non-toxic pool antifreeze (propylene glycol-based)
  • Above ground winter cover and heavy-duty winch cable
  • Cover air pillow and inflation pump
  • Wrench set, screwdriver, and pliers for equipment disconnection
• Mandatory Prerequisite Knowledge & Standards:
  
  
  • Complete the closing process only when consistent water temperatures drop below 65°F (18°C) to prevent algae blooms during late-fall warm snaps.
  • Never completely drain an above ground vinyl-liner pool; hydrostatic pressure shifts or liner shrinkage will cause irreversible structural failure.
  • Verify local electrical codes before unplugging and storing pump motors.
• Estimated Budget & Duration Benchmarks:
  
  
  • Budget: $100 to $250 for chemicals, winter covers, Gizzmo plugs, and antifreeze.
  • Duration: 3 to 5 hours of active labor, split across cleaning, chemical balancing, and hardware winterization.

Step-by-Step Above Ground Pool Winterization

Step 1: Deep Clean and Vacuum the Pool Floor

Remove all ladders, solar blankets, skimmer baskets, and hanging pool accessories from the water. Scrub the pool walls thoroughly with a nylon-bristled brush to dislodge microscopic algae spores and organic film. Run your pool vacuum manually to extract all accumulated debris, silt, and leaves from the pool floor.

Pro-Tip: Clean the pool while the water is still warm enough for comfortable work, but do not wait until leaves stop falling entirely; use a fine leaf net daily leading up to closing day.

Step 2: Balance the Water Chemistry

Test and adjust your pool water chemistry to prevent staining, scaling, and corrosion throughout the winter months. Set the pH between 7.2 and 7.6, total alkalinity between 80 and 120 ppm, and calcium hardness between 175 and 225 ppm. Add a strong dose of non-chlorine shock or winter oxidizing shock, followed by a concentrated, copper-free winterizing algaecide to inhibit biological growth.

Warning: Never add chlorine shock and algaecide simultaneously; high chlorine levels will neutralize the algaecide. Allow the pump to run for 24 hours after adding shock before introducing algaecide.

Step 3: Lower the Water Level and Drain Equipment

Lower the water level below the skimmer return or to the manufacturer-recommended level—typically 4 to 6 inches below the skimmer faceplate if using a skimmer cover plate, or below the return jet if removing all pool plumbing. Disconnect the hoses running between the pool, pump, and sand or cartridge filter. Open all drain plugs on the pump, filter tank, and chlorinator to completely evacuate trapped water, then store these components in a dry, frost-free location like a shed or garage.

Step 4: Protect Plumbing Lines and Skimmer

Blow out remaining water from underground or flexible hoses using a shop vac or air compressor if your setup utilizes them, or remove hoses entirely and store them flat. Apply Teflon tape to a threaded winterizing Gizzmo and screw it directly into the skimmer bottom port to absorb ice expansion pressure. Insert a rubber expansion plug with a stainless steel bolt into the return jet fitting from inside the pool wall, and pour a cup of non-toxic RV antifreeze into the skimmer housing for added protection.

Step 5: Install the Air Pillow and Winter Cover

Inflate a heavy-duty vinyl air pillow to roughly 60-70 percent capacity and place it securely in the direct center of the pool using the provided tie-down grommets. Drape the winter cover evenly over the pool surface and the central pillow, ensuring a balanced overhang around the entire top rail perimeter. Thread the steel cable through the eyelets of the cover, insert it into the winch mechanism, and crank it tightly to secure the cover against high winter winds.

Winterization Methods and Material Comparison

Choosing the correct chemical regimen and hardware protection depends on your regional climate severity and pool construction type.

Common Site Failures and Field Fixes

• Root Cause: The winter cover collapses into the center of the pool during heavy snow or rainstorms.
  
  
  • Actionable Fix: The air pillow likely deflated or was over-inflated. Replace the pillow, inflate it to only 60 percent capacity so it flexes under pressure, and retighten the perimeter winch cable.
• Root Cause: Green, swampy water develops by early spring despite closing chemicals.
  
  
  • Actionable Fix: Closing chemistry was added too early while water temps were above 65°F, causing sanitizers to dissipate. Shock the pool immediately with liquid chlorine, run a submersible pump to circulate, and brush the walls.
• Root Cause: The skimmer body cracks horizontally along the plastic housing.
  
  
  • Actionable Fix: Water leaked into the skimmer and froze without a Gizzmo expansion bottle installed. Replace the entire skimmer housing and faceplate gasket before opening next season.
• Root Cause: The vinyl liner slips out of the coping track during winter winds.
  
  
  • Actionable Fix: Use a hair dryer or heat gun on a low setting to gently warm and soften the vinyl liner, then carefully lock it back into the bead receiver using a blunt plastic liner lock tool.

Frequently Asked Questions

Should I drain my above ground pool completely for the winter?

No, you should never drain an above ground pool completely. The water weight maintains structural integrity against outside soil pressure and prevents the vinyl liner from drying out, shrinking, or cracking. Maintain water levels according to your specific winter cover and skimmer setup guidelines.

When is the exact right time to close an above ground pool?

Close your pool when the local sustained water temperature drops below 65°F (18°C). At this threshold, biological activity and algae reproduction halt significantly, ensuring your closing chemicals remain effective until spring opening.

Do I need to run my pool pump all winter long?

No, running a pump during freezing weather risks catastrophic motor cracking and pipe freezing unless you maintain continuous, specialized freeze-protection automation. Standard above ground pool winterization requires completely shutting down, draining, and storing the pump and filter system.

How do I keep rainwater and melting snow off the winter cover?

Use a specialized cover pump or a siphon pump to periodically remove standing water from the top of your winter cover. Excess weight from unmanaged water can pull the cover into the pool, contaminating the clean water underneath.

Can I use regular household antifreeze in my pool plumbing lines?

Never use automotive antifreeze (ethylene glycol), as it is highly toxic to humans, pets, and local wildlife, and it can damage pool liners. Always purchase certified, non-toxic propylene glycol-based RV and pool antifreeze for plumbing protection.

Ensure your pool investment survives the freezing months with high-grade winterizing accessories and precise chemical management. Explore our professional catalog of pool closing kits, winter covers, and heavy-duty hardware to secure your backyard oasis today.