How to Close an In Ground Pool for the Winter

Why You Should Close Your Pool for the Winter?

Ideally, you should close your pool before it gets too dirty. Having a pool cover that has a toxic mix of algae, debris, and white mold will not only make it look unappealing, it will also damage your pool's system.

Not only will it help keep your pool cleaner, it will also help keep it running smoothly. It saves you time and effort, and it can help avoid costly repairs.



When the temperature stays below 65 degrees, leave your swimming pool open until the weather cools down below that point. This will help keep the algae in your pool at bay for the winter.

If you have a few warm days during the winter, you can treat your water to prevent algae. This will give you a leg up when you open your pool next season.


You'll Need That Gear

This year, make sure to stock up on all of the gear you need. You can use it next year if you need to.
  • Winter pool cover
  • Pool brush
  • Pool vacuum or robotic cleaner
  • Winter pool plugs for return jets
  • Skimmer plug
  • Shop-Vac or air compressor
  • WinterPill
  • Tools for removing pool accessories, like ladders
  • Winter pool cover pump

The Chemicals

If you do not have these, then it’s time to update your inventory. Just go to the list below and add any of these to your inventory.

  • Water test strips
  • Chlorine or your choice of sanitizer
  • pH increaser
  • pH decreaser
  • Alkalinity increaser
  • Calcium hardness increaser
  • Algaecide
  • Pool shock
  • Metal sequestrant
  • Cyanuric acid
  • Antifreeze for Pools
  • Pool Enzymes


10 Detailed Steps On How To Close Your In-Ground Pool

Getting started is the first step in getting your pool back in working order. It’ll take a few minutes to get going, and it’ll be worth it in the long run.


Step 1: Clean Your Pool

Use a brush to scrape the bottom and sides of your pool to remove algae from the surface. It will also help dislodge the algae spores that might develop into a bloom if left alone.

A good vacuum cleaner will remove algae, dirt, and debris from your pool floor. It can also pick up any residue that might have accumulated from the previous season.


Step 2: Test Your Water

Since your pool is closed, your water should be balanced. Doing so will give it a serious boost up throughout the winter, and it will protect it from the elements.

Your pool's balance is crucial to its longevity and protection from corrosion. It's also important to make sure that the chemicals in your pool are balanced to prevent them from becoming too concentrated.


Step 3: Add Chemicals

Aside from algaecide, another thing to consider is the presence of metals in the water. If your pool has high levels of these, add a dose of metal sequestrant.

Some chemicals can also help boost the chlorine in your pool. They can also help remove algae from the water. WinterPill is a great chlorine clarifier that dissolves quickly.


Step 4: Shock Your Pool

Since outdoor pools can be very dry, it’s time to shock them. However, make sure that they’re at least 8 hours away from being destroyed by the sun before going to bed.

If you have algae blooms that have just been vacuumed up, you can increase or decrease the amount of shock that you use.


Step 5: Drain Part of Your Pool Or Don’t

Getting your water level lowered can help prevent freezing damage. Just make sure that the water line is where you want it to go.

Since a pool cover needs water to keep up with the weight of the snow and debris, it should be lowered a couple inches to the bottom of the skimmer. If you have a vinyl liner, lower it one inch to a non-vinyl liner. If you have a pool cover that's automatic, lower it another six inches to a non-plastic pool cover.


Step 6: Pump and Filter

Your filter is a holding device that's designed to collect all the gunk that's floating around in your water. It's important to keep it running smoothly and free of contaminants before you renew it.

No cleaning is needed for cartridge filter cartridges. Just take them out and submerge them in water with a pool filter cleaner.

It’s time to clean your diatomaceous earth and sand filter. This will help remove all of the water from the system.


Step 7: Get That Water Out

Getting used to not swimming is an important step in getting healthy.

This step will help keep your pipes from freezing. You'll need to use an air compressor to remove the water from the lines. You can also use a ShopVac to clean the pipes.

How to Blow Out Your Plumbing Lines:

1. Remove all skimmer baskets and return fittings, which look like giant screws around the diameter of your pipes.

2. Remove all the drain plugs from your filter system.

3. Set your multiport valve to “recirculate.”

4. Attach your ShopVac or air compressor (and an adapter, if needed) to the pump’s drain plug opening and blow air through the system.

5. Watch for bubbles to come out of the system via the return lines and skimmer.

6. Use your ShopVac to remove water from the skimmer until it’s dry.

7. Insert a skimmer plug into the hole at the bottom of the skimmer.

8. Insert winter pool plugs in the return lines as you see air bubbles coming out of each one.

9. Turn the valve in front of your pump to the main drain setting to move air toward the main rain, and watch the deep end of your pool for bubbles. Let it run for about a minute.

10. Turn your pump valve back to the skimmer line, shut off your air compressor, and put a valve in your pump to prevent leaking. You’re done!


Step 8: Remove Those Accessories

Having the pool cleaned out will help prevent debris and prevent further damage. Also, it's a great opportunity to get rid of any ladders, rails, and other pool accessories that are no longer needed.

Since you didn’t need to blow your lines out, you can now clean out your skimmer baskets and remove the return fittings from your jets.

Do you have a saltwater pool? This is the time to get rid of the chlorine generator and install a new one.


Step 9: Install a Winter Cover

Winter covers are great for keeping your pool water clean and safe from debris and contaminants. They can also help keep the chemicals in the water without causing it to get seriously contaminated.

Winter covers are usually constructed with tubes or weights to keep the water in the pool from sinking. They also tend to keep the pool water balanced by covering it in sand or other materials.


Step 10: ... and Look Forward For The Next Season!

After another great season, it’s time to get back to work. Take the time to close your pool right, and the first day of the pool season is going to be a breeze.



This post was originally published on Pool Parts To Go


If you have any other questions about pool and spa products please do let us know - we are here to help!

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