Winterizing Above Ground Pools

Winterizing above ground pools is an important step when it comes to closing down a pool for the winter season. As water sits stagnant over the winter including before and after the water freezers, water can develop potentially harmful bacteria and develop stubborn stains as it falls out of chemical balance. The good news is there are a few simple steps you can take, and a few things you can add to the water at the end of the pool season that will make above ground pool opening in the spring a breeze and even save you time and money in the long run. 

winterizing above ground pools

It might seem a bit confusing if this is your first time closing a pool but it's important whether you have a salt water pool or a regular chemical chlorine pool. Whether you are shutting down your pool for a few months or extended periods of time this guide can be used to get any above ground pool ready for weeks and months of no water circulation. The easiest way to close an above ground pool is to use a winterizing kit that has everything you need including a shock, clarifier and anti-stain which we're going to go over below. 

Above Ground Pool Winterizing Kits

When winterizing an above ground pool the easiest way is to use a kit with pre-measured amounts of the chemicals required to keep the water sanitary while it's not being used. Even a perfectly balanced pool heading into the winter season should be given a chlorine boost in the form of a shock as well as a stain preventer clarifier and algaecide. There's nothing worse than stubborn stains that need to be cleaned in the spring or removing the cover to find a pool full of algae blooms.  

Robelle Above Ground Pool Winterizing Kit

The Robelle Above Ground Pool Winterizing Kit is an excellent choice as an all-in-one chemical closing bundle that has everything you need at an affordable price. Included in the kit is a 1 quart winterizer, 2 pound winter shock and a 1 quart anti-stain controller. The kit is available in bundles that treat pools up to 10,000, 15,000 or 30,000 pounds respectively that vary in the amount of each product. There's no tools required you simply add the products to the pool water as directed by the manufacturer which makes closing super easy with the added assurance and peace of mind.

Winterizing Above Ground Pool Step by Step

Above ground pool closing and winterizing can be done by any handy pool owner by following these steps and working through each one carefully. If you have given yourself a couple of weeks before you experience cold or freezing temperatures you have plenty of time to get your pool closing steps completed. It might take a bit of time to get everything in order the first time you close your pool but it will become a lot more simple after you're gone through and done it once. 

1)  Final Balancing

A week or two prior to closing your pool make sure that you balance the water chemistry as best as possible. The more balanced you get your pool water the more effectively the winterizing chemicals will work to keep your pool water stable. If you want more information about chemical balancing be sure to visit our salt water pool maintenance page. The ideal ranges for above ground pools are as follows but you shouldn't need much adjusting if you have kept your pool healthy all season long.

  • Salinity: 2500-4500 ppm
  • pH: 7.2-7.8 ppm
  • Free Chlorine: 2-4 ppm
  • Alkalinity: 80-120 ppm
  • Cayanuric Acid: 50-80 ppm
  • Calcium Hardness: 200-400 ppm

2)  Final Cleaning

After you have balanced and double checked that your water is ready for the winter closing it's the perfect time to give your pool a good clean. If you leave grime or residue on a vinyl liner while the water is sitting stagnant it is likely to stain and be very difficult to remove even with the strongest cleaning brush. If you find that you need a bit more than a brush there are excellent biodegradable cleaners available or you can use an above ground pool vacuum for additional cleaning.  

3)  Chemical Balancing

This is probably the most important step when winterizing above ground pools because of the tendency of water to turn unhealthy over the winter especially if you have temperatures that fluctuate around the freezing point. A pool winterizing chemical kit will have the key components including an algaecide, sequestering agent and oxidizer. If you don't add these chemicals you run the risk of your water turning ugly quickly when conditions become ideal for algae or other micro organisms to flourish and grow uninhibited.

4)  Lower Water Level

After you have your pool balanced and winter chemicals added you should drain your pool water level to approximately 6 inches below the skimmer line and return jets. Never completely drain your pool because it will make your pool more susceptible to damage during the winter. Check local bylaws about where pool water should be drained, you may need to connect a drainage hose that can reach to wherever the water needs to be drained. 

5)  Hardware Preparation

After the pool itself and the water is sorted out it's time to take care of any of the hardware that keeps your pool running smoothly all year long. The main power supply should be turned off before disconnecting any plumbing from the filter pump, skimmer and salt water system. All valves should be removed to allow for complete draining and left open to allow for air circulation and evaporation so you don't have any water left that could potentially cause damage. 

You may need to use an industrial blower or shop vacuum to forcefully blow out the water that won't empty from the plumbing. All plumbing should be refastened after allowing the water to evaporate completely and anywhere that is open to the elements should be plugged with an expandable rubber plug or similar. If you have a cartridge filter, remove and clean the cartridges and the same goes if you have a diatomaceous earth filters. If you are using a sand pool filter you should run a backwash to clean out the filter sand and if necessary do a complete rinse of the sand.

6)  Salt Cell Preparation

If you have a salt water pool system you should set the chlorine generator to the winter setting if available. If your chlorine generator doesn't have this feature you will need to remove the cell or system and store inside over the winter. Most chlorine generators have a removable electrolytic cell that can be removed by unscrewing the end caps and removing the cell inside. The winter is a good time to clean the salt cell and gets you in the habit every time you carry out your winterizing above ground pool steps.  

7)  Remove and Store Accessories

This step can be done at any time but it should not be skipped if you want to prolong the life of your pool hardware. All accessories including anything attached to your pool that can potentially be damaged by extreme weather should be removed. Items that should be stored inside include pool accessories, steps, ladders and toys. It's also a good idea to give everything you're storing away a good clean to prevent staining.

8)  Air Pillow

When winterizing above ground pools that experience freezing temperatures this step shouldn't be skipped. Placing a winter pool cover air pillow that floats on the water in the center of your pool will distribute the stress caused by the freezing water and prevent any damage from the expansion process. An air pillow is a great idea for pool owners that experience freezing temperatures and a necessity in areas temperatures below 14 F (-10c).

9)  Winter Cover

A good quality cover that fits your pools dimensions as close as possible should be installed and tied down securely. You may find that cover clips are necessary to prevent the cover from coming off in areas that experience strong winds and extreme temperatures. A good above ground pool cover will ensure that all the hard work you put into cleaning the water pays off by not allowing any dirt or debris to get in your pool.

We hope this guide to winterizing above ground pools helps you achieve a clean, fully functioning pool in the spring. Always refer to the manual provided with your equipment for detailed instructions that can be different and specific to your pool system or hardware.


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