How To Winterize An Inground Saltwater Pool

Nick Durante
by Nick Durante

It’s a tough time of the year when you have to say goodbye to your swimming pool until the spring or summer. Closing a pool can be intimidating and difficult because of how much can go wrong if you skip a step. Because of that, many homeowners struggle with how to winterize an inground saltwater pool.

You need to clean the surfaces in your pool and balance the pH level when you winterize an inground saltwater pool. Make sure that the salt level is at 3,200 ppm before you place the cover on your pool to close it. Empty the filter and chlorinator when you close your inground saltwater pool so that the pipes don’t freeze.

Some homeowners use pool pillows to support the pool cover in case of rain and ice. Luckily, your underground pool pipes are unlikely to freeze if they are 2 feet or more below the ground. Follow along as we explore how to winterize an inground saltwater pool.

How do you Close a Saltwater Pool for the Winter?

You need to clean, balance, and add chemicals to your saltwater pool for the winter. Each of these steps is critical to your pool’s health and will determine how it looks when you reopen it in the spring or summer. The chemical balance, pH level, and surface cleanliness all contribute to a healthy pool before you cover it.

Many homeowners forego professional help and winterize their inground saltwater pool themselves. Let’s take a look at the steps you need to follow when you winterize an inground saltwater pool.

1. Clean Your Pool

Cleaning is the most important step to winterize an inground saltwater pool. Thoroughly vacuum and brush the surfaces of your pool to eliminate dirt and grime. Debris can easily settle on the walls and floor of your saltwater pool during the spring and summer.

Make sure to clean your pool basket as well so that debris doesn’t make its way back into the pool once you cover it. Treat your pool with algaecide before you close it if you have problems with algae. Otherwise, the algae will thrive once you cover and winterize it for the winter.

2. Balance the pH

The pH level of your saltwater pool is critical to its overall health. Test the water to make sure that the alkalinity is between 80 and 120 ppm (parts per million) as well. Calcium hardness is another key factor that many homeowners overlook when they winterize an inground saltwater pool.

A healthy calcium hardness for your pool water is anywhere between 200 and 400 ppm. The last thing that you want is excess calcium and magnesium in your saltwater pool before you winterize it.

3. Moderate the Salt Level

Excessive salt in your pool water when you winterize can be harmful to your pool. You can find salt strips at any pool maintenance store, and they are your friend when you winterize an inground pool. Different manufacturers provide a recommended salt level to their customers that vary between brands.

Contact the manufacturer if you are unsure of the ideal salt level when you winterize your pool. On average, the ideal salt level is 3,200 ppm and you don’t want to exceed that when you close the pool. That means that you need to wait to close your saltwater pool if the salt level is too high.

Never add more salt if your pool is at or near that threshold when you winterize it. Otherwise, you risk reopening your pool and finding salt damage and sediment.

4. Empty Filter and Chlorinator

Empty your pool filter and chlorinator so that they won’t freeze during the winter. Unplug the automatic chlorinator if you have one so that it doesn’t get damaged when not in use. Otherwise, you may need to replace this expensive piece of equipment when the spring and summer roll around.

Make sure that there is no water left in the chlorinator or it could eventually form a deadly gas. Check your pipes or hire a professional to make sure that no water remains. The water could freeze during the winter and damage the pipes and you’ll need to replace them next year.

Luckily, you can do this without professional help if you simply use a shop vac. Place the shop vac nozzle over the pipe opening to suck out the remaining water.

5. Prepare the Water

You must prepare the water with chemicals and enzymes when you winterize an inground saltwater pool. Pool-closing kits come with all of the chemicals and enzymes that you need to protect your pool. This includes algaecide, chlorine-free shock, and stain preventers in most cases.

Save this step until you are almost ready to place the cover on your pool for the best results. That way, the chemicals will be at a strong concentration right before the cover goes on. Otherwise, the chemicals may be too weak and less effective when you cover your pool.

6. Install the Cover

You can’t winterize an inground saltwater pool if you don’t place a cover over it. The cover will keep the chemicals in the water intact and keep debris out of the pool. Ideally, you should have 2-3 people help you install the pool cover so that it stays straight and intact.

Stake the cover at each corner of the pool so that it stays in place. Many homeowners put pool pillows in the water before they place the cover on. They work to provide a base for the cover so that it doesn’t sage too much.

However, pool pillows are typically only necessary if you live in an area with lots of rain and ice. Otherwise, your pool cover won’t naturally sag unless it is damaged, poorly installed, or outdated. Pool covers generally start at $1,000 and they are necessary to winterize your pool.

How far do you Drain an Inground Pool to Winterize it?

Make sure that you drain the water in an inground pool to at least 4” below the skimmer. Ideally, you should drain the water to 6” below the skimmer, but that’s not necessary in all cases. You never want your pool water to be too close to your skimmer when you winterize an inground pool.

The skimmer and pipes can become damaged if the water freezes when it is level with them. Make sure that the water is below the jets in your pool as well so that internal damage doesn’t occur.

Will Underground Pool Pipes Freeze?

Underground pool pipes can freeze if the temperature stays consistently below freezing for several days. The pipes beneath the ground have the benefit of extra insulation which helps protect them. That is why it takes a few days for them to freeze during extremely cold temperatures.

This is mostly only common in areas with harsh winter weather. Pipes that are more than 2 feet below ground are less likely to freeze because of the extra insulation. However, underground pipes are more likely to freeze quickly if you don’t winterize your inground pool.

What Chemicals are Needed to Close a Saltwater Pool?

Chemicals such as algaecide and chlorine-free shock are necessary when you close a saltwater pool. Avoid shock that contains chlorine when you close a saltwater pool. The combination of salt and chlorine can become quite dangerous when enclosed.

Wait to shock the pool until 2 days before you close a saltwater pool for the best results. Stain treatment chemicals are also needed to winterize an inground saltwater pool. This will reduce the risk that salt will stain the floor and walls of your pool.

What Happens if you Don’t Winterize Your Pool?

Your pool can become riddled with algae if you don’t winterize it. The pipes in your pool can also freeze and potentially burst if you don’t drain and treat the water. Your chlorinator and skimmer can break as well which costs hundreds of dollars to replace.

The water can become dangerous if you fail to winterize your pool. Algae, bacteria, debris, dirt, and even pests will thrive in the water. This will result in hours and hours of necessary maintenance when you reopen it later on.

It is unsafe to swim in a pool with green water when you open it. The best way to avoid this problem is to winterize your pool and treat it with algaecide before you close it.

Summing it Up

The first step is to clean and scrub the surfaces in your saltwater pool to winterize it. Balance out the pH level to 80-120 ppm and drain the water until it is between 4” and 6” below the skimmer and jets. Treat your water with chlorine-free shock and algaecide so that it’s in great shape when you reopen the pool.

Put pool pillows in your water if you live in a climate with harsh winters. They will help to support the weight of your pool cover when there is rain and ice on it. Hire a professional or enlist the help of 2-3 people before you place the cover on your inground saltwater pool.

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Nick Durante
Nick Durante

Nick Durante is a professional writer with a primary focus on home improvement. When he is not writing about home improvement or taking on projects around the house, he likes to read and create art. He is always looking towards the newest trends in home improvement.

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