Closing

Improper closing can lead to many problems the following year. By winterizing your pool correctly, you can protect all mechanical and chemical components and make next spring’s opening easier and less expensive.
Step one: Pack everything up
Remove and disconnect (or cover with builder’s plastic) any slides, ladders, diving boards and maintenance equipment and clean off any debris that could stain pool surfaces. Scrub tile along the waterline and vacuum the pool walls and floor. Then, lower the water level to approximately 457 mm (18 in.) below the top edge of the pool (51 to 76 mm [2 to 3 in.] below the return fittings). Do not drain all of the water as this can cause pool walls to heave and crack over the winter. Blow and cap all lines in sequence and ensure caps are tight enough to prevent accumulated water from leaking back into the lines. If there is enough cord to let them settle on the bottom of the pool, you can also remove lights from their niches. Do not attempt to remove floating underwater lights; instead, hire a certified electrician.
Step two: Shut down the equipment
All equipment needs to be completely drained to prevent freezing damage.
Pumps/filters
Set the dial to the ‘winterize’ position, if applicable. If this option doesn’t exist, set the dial between any two positions. Remove and store the filter drain cap, pressure gauge and sight glass and remove the drain plugs from the pump.
Heater
Carefully follow the manufacturer’s directions to shut down the unit and remove the drain plugs. Before reinstalling the plugs, grease the threads and disconnect the pressure switch from the siphon loop tubing. Also remove any remaining water from the heat exchanger using compressed air or a wet/dry vacuum.
Skimmer and returns
Remove the skimmer basket and clear water from the skimmer and main drain lines. If the skimmer has two holes, plug it into the main drain hole (usually the one closest to pool). You can also add a specially designed pool-safe anti-freeze to the skimmer and pump to prevent collected water from freezing and causing damage. Remove the pool jet from the returns and remove water from the lines; then, plug the returns. Also clear and plug any side suction or automatic cleaner lines.
Chlorine generator
Drain any water from the unit and disconnect the tubing in off-line models. Remove the cell from the generator and clean it.
Step three: Balance water chemistry
Before closing, take a water sample for analysis at your local pool store, where you can get advice on how to balance your water for winter (these parameters will be far different than summer settings). Prepackaged winterizing chemical kits are also available and include sequestering agents that address mineral issues (e.g. copper, manganese and iron), algaecide to prevent algae growth and a chlorine shock for oxidizing contaminants.
Step four: Install a cover
Covers don’t just keep unwanted debris out of your pool. They also serve as a safety barrier during the off-season. Look for a cover made of mesh material or equipped with a pump that automatically drains any collected water. The three basic cover options are:
- a water bag cover (a tarp held in place by vinyl bags filled with water);
- a lock-in fabric cover (held in place by beading and attached to your pool’s coping; and
- a safety cover (porous, woven material stretched over the pool, attached with straps and springs or operated automatically).
With the cover installed, take a quick survey of the pool area and make sure all unnecessary equipment is turned off has been, including the electrical breaker and gas. All that’s left is to bundle up, sit back and wait for the next swimming season to arrive.