Locate all your winterizing supplies. This should include the cover, the air pillow, the plugs for the skimmers ( gizzmos or rubber plugs ), the winter plate ( if used ) and your winterizing chemicals. You need these items for proper winterization. If you are using the green Gizzmos to plug your skimmers, check them out and make sure that they are not cracked. This is very important when dealing with gizzmos. Gizzmos with holes or cracks will not work !
Backwash the filter very well to clean it out. Drain DE filter tanks and leave backwash valve open. On sand filters, unplug the filter drain plug and leave off. Put drain plug with other removed items in the pump basket. Make sure multiport valve ( if any ) has no water in it. Blow it out with a compressor or shop vac if necessary. Please note that it is not recommended to “acid wash” DE filters at the time of the pool closing. This is best to do in the Spring so that you can immediately run pool water through the system. It is not good to use muriatic acid on a DE filter and then just rinse it off and put it away. The acid may degrade the filter parts over the winter.
Plug return pipes and skimmer ( see # 5 for skimmer details ) and remove all hoses.
Disconnect your pump and filter. Make sure that pump is totally drained out of any water. Turn pump upside down once to make sure ! Remove any drain plugs from the pump. It is a good idea to store any small plugs or parts in the pump basket. This way you will be able to find them easily in the Spring. Store in a shed or garage.
Some people like to remove the skimmer box and install a winter plate with gaskets. If you do this, make sure it does not leak. Yes, you will get wet doing this ! Most people simply plug the skimmer hole with a black rubber plug or a gizzmo. It is easier. You can let the water in the pool go down to the bottom of the skimmer if you like – then you do not have to plug the hole at all. This method is also OK, but realize that the pool cover will sit lower in the pool – therefore you might want to use a cover that is one or two sizes bigger than your pool so that you have the extra material available. Any of these methods are OK – it is mainly personal preference.
Blow up and install your air pillow. Air pillows are usually used but are not absolutely necessary. They are a good idea in case the water in the pool freezes, expands, and breaks the pool wall. The pillow takes up the slack. However realize that this is somewhat rare. If no pillow is available, you can use tires, tubes, balls, or other air filled floating objects. Throw them into the pool to take up ice expansion. Tie air pillow at two places and position in center of pool. Tie strings to the pool wall so the pillow does not move during cover installation. If the pillow is leaking, either patch it or get a new one. Remember…the pillow is there to take up any expansion of the water which may occur due to freezing and possibly causing the above ground pool wall to split. Pillows are NOT to keep the rain water out of the pool cover. They will not do that. The rain water will always settle around the outside of the pillow.
Remove all deck equipment from pool, if any (ladders, rails, slides, etc.).
Add chemicals. Mix any granular winterizing chemicals in a bucket so that they are totally dissolved. Dump mixture into the pool. You want to avoid any undissolved granules from settling on the pool floor and staining the liner. This is very important. If you are using any liquid winterizing chemicals, pour them in the pool as well. Test the pool for pH and Total Alkalinity. Adjust to normal levels using pH PLUS or MINUS and ALKALINITY PLUS. pH should be between 7.2 – 7.6 and Alkalinity between 100-150 ppm. Make sure one of your winterizer chemicals consists of a SHOCK-type product. You want the chlorine level in the pool to be rather high (over 3.0 for wintertime).
Place cover on pool and secure. Make sure that cover cable wire is tight so that cover does not blow off or fall in pool. Make sure the pillow is still in the middle of the pool after cover installation. If not, reset cover and pillow.