How to Winterize a 15-Foot Vinyl & Metal Frame Pool

Shock your swimming pool based on your water capacity. Allow the filter to run for 24 hours. Test the water and balance the chemicals as indicated by the pool testing kit. Before you close the pool, make sure the chlorine, alkalinity and pH levels are all in proper balance. If you maintained your pool properly all season, this shouldn't be a problem.

Backwash the filter as per your filter's guidelines, depending on the type of filter you own. Turn off the filter and switch the multiport valve on your filter to the "drain" setting. Allow the water to drain to just below the skimmer.

Unscrew the return jet assembly and store away for the winter. Replace the assembly with the return jet plug. Tighten the plug with the turn-screw mechanism.

Apply the skimmer cover plate to the skimmer opening. Some covers snap on, while others have to be screwed into the skimmer frame. With the skimmer and return jet plugged, fill the water back up to normal levels. You will lose water due to evaporation during the winter, so it's a good idea to refill the pool.

Position the inflated air pillow in the center of the pool. Hold the air pillow in place with ropes tied to the pool railing. The air pillow deflects the water to the sides of the cover so that it does not collapse and release tension from the pool walls.

Place the winterizing kit into the water. Most common above-ground pool winterizing kits come assembled in a plastic canister that is suspended at mid-depth in the pool. Follow manufacturer's instructions for proper placement of the winterizing kit as they can vary. Tie the winterizing kit string to the air pillow string.

Remove the ladder. Apply the pool cover evenly across the surface of the pool. You will need at least two people to place the cover correctly. Tuck the cover under the pool railings. Tighten the cover's rope with the turn mechanism.