How to Winterize Your Pool

Need some tips on how to close your pool for the winter months? Use this guide to make sure you're covered in all spots.

Whether you live in the Snow Belt or the Sun Belt, a pool can provide hours of fun and good exercise for friends and family. There’s nothing like getting out of bed on a summer Saturday, getting right into your bathing suit, and spending a morning, or an entire day, in and out of the water. Or maybe you prefer to wait until everyone’s in bed for a solitary swim. Either way, proper pool maintenance makes it possible.

If you live in a cold climate, closing your pool for the winter means getting it and the water as clean as possible, draining all plumbing and filters, and covering the pool for the season. If you live in a warm climate, closing your pool doesn’t require as much work, and you may not even want to close it at all, unless you need a break from pool maintenance for a few months, of course! Follow this step-by-step guide to winterize your pool, so you can continue to enjoy it year after year.

Balance and Shock

The first step towards winterizing your pool is to balance the water chemistry and add chlorine or non-chlorine shock. About a week before you close your pool for the winter, adjust the water pH levels to between 7.2 and 7.4, the alkalinity to between 80 and 120 ppm, and the calcium hardness to between 180 and 220 ppm. Add chlorine or non-chlorine shock at least several days before adding algaecide or covering your pool. High chlorine levels can damage your pool cover and counteract the effects of algaecide. Let the chlorine level drop down to 1.0-3.0 ppm before adding any winter algaecide to your pool.

Check and Clean the Filters

If you don’t clean your filters before you close your pool for the winter, you could open it up to a nasty green surprise come spring. If you’re using diatomaceous earth (DE) filters, though, you’ll need to keep up with your monthly filter cleaning throughout the winter. You’ll also need to clean them thoroughly at least once over the winter.

Get It Sparkling Clean

Get your pool as clean as you can before you cover it for the winter. If you live in a warm, sunny area and don’t plan on covering your pool, you should still skim, scoop, vacuum and brush it throughout the winter to keep organic matter from building up in it and promoting algae growth. If your pool already has a lot of algae and silt buildup, vacuum the pool waste and then brush and skim it again before putting on the cover. To get your pool as clean as possible, run your pool filter 24 hours a day for a few days before completing winterization.

Put on the Cover

A pool cover helps keep the water chemistry stable and prevents debris from falling into it over the winter. If you live in the Snow Belt, covering your pool during the winter is a must. If you live in the Sun Belt and want to close your pool for the winter, a pool cover can help you avoid the need to scoop, skim and vacuum. 

Lower the Water Level

If you live in an area where temperatures get below 41℉ in the winter, you need to lower the water level before closing your pool. You should pump water out of your pool until the water level is about a foot below the skimmer. Lowering the water level allows room for water to expand in your pool as it freezes, which can prevent damage.

Lower the water level only if you’re closing your pool down entirely until spring. If you live in a warm climate and plan to still use the pool occasionally over the winter, you can leave it full of water. 

Blow Out the Plumbing

In the Snow Belt, water in the pool pump, heater, filter, and chlorinator can freeze over the winter and damage these parts irreparably. While American Home Shield® does provide home warranty plans for pool pumps and spas, the easiest and cheapest thing to do is simply to drain all the water out of your pool plumbing so you don’t have to arrange for an unnecessary pool pump replacement or other plumbing repairs that may not be covered by your pool pump and spa plan. 

Remove drain caps and plugs from your pool pump, filters, heater and chlorinator, and let the water drain out. Use air from an air compressor or shop vac to blow out water remaining in the lines. Leave the drain caps off so any water that finds its way into the equipment over the winter can drain out.

Remove and Store Accessories

Remove ladders, skimmer baskets, solar blankets, cleaners and wall fittings, and store them in a safe, climate-controlled area, along with your drain caps or plugs and any other pool accessories, like chlorine tablets, poles and nets. Freezing temps will damage plastic pool accessories and could even ruin them.

An unwinterized pool will freeze in many parts of the country, and the expanding ice could destroy the pool itself and the plumbing that keeps it operational. Even if that doesn’t happen, debris that is allowed to fall into an unsupervised pool over the winter can cause algae to grow in the water and dirty your pool. Take the time to close your pool down properly, and let us worry about repairing or replacing your pool’s pump motor and plumbing as needed. Learn more about our pool and spa home warranty coverage.