Winterizing Your Swimming Pool at the End of the Season
Follow these steps for winterizing your swimming pool to ensure that you get off to a good start next summer.
First make sure the swimming pool water is balanced (i.e., pH, chlorine, total alkalinity, and calcium hardness levels) before closing the pool for the winter.
- Test the water using a suitable test strip or liquid test kit.
- Adjust the total alkalinity and pH as needed, and raise the chlorine sanitizer level to 3 ppm.
- Brush the pool walls to dislodge all visible debris.
- Add a stain and scale control product according to label directions.
- Add a winterizing algaecide according to label directions.
- Run the filter for 8–12 hours.
Note: If winterizing the pool in one day, run the filter for a minimum of 2–4 hours.
- Vacuum the pool to remove any debris settled on the bottom.
Note: Vacuum only when the water is clear and the bottom of the pool in the deep end is clearly visible.
- Backwash the filter thoroughly.
- Drain the pool water below the skimmer and inlet lines (sometimes this can be done while vacuuming).
- If there is a chlorine feeder connected to the pool, make sure that there is no remaining product in the feeder. Clean and flush the feeder per manufacturer’s directions or run filter until all remaining product has been dissolved.
- Disconnect the filter components and prepare them for winter per manufacturer’s directions.
- If your pool has a cartridge or rechargeable media filter (Perlite or DE), clean the filter thoroughly using a hose equipped with a spray nozzle.
- To prevent freezing, the suction and return lines must be blown out to remove standing water, and then plugged with special winterizing plugs to prevent them from refilling with water.
Note: Water remaining in the plumbing lines over the winter can freeze and potentially damage the plumbing, resulting in leaks.
- Add a winterizing dose of shock oxidizer containing DuPont™ Oxone® to oxidize organic compounds in the water. Follow the label directions for winterizing (2 pounds per 10,000 gallons).
- Cover the pool with a solid cover, and secure with water bags.
What to Do Where the Winters Are Mild
- Run the filter for a minimum of 2 hours every day, or as needed to maintain good water quality.
- Thoroughly brush and vacuum the pool as needed.
- Clean the skimmer baskets regularly.
- Monitor the pH, chlorine, total alkalinity, and calcium hardness levels with a suitable test strip or liquid test kit. Adjust the levels as necessary.