When it comes time to close your swimming pool for the year it is important to consider a number of different factors. The most important thing that you want to do before you close your pool is be sure to clean the pool completely so that there is no leaves or debris in the bottom of the pool and the water should be crystal clear with a measurable chlorine count.
Clean The Pool
If you do not take the time to clean your swimming pool before you close it for the season you'll find that the start up of the pool next spring will be much more difficult. There will be a great deal of algae that has grown over the winter season as a result of the organic debris that was left in the pool at the time of closing. The organic debris uses up the sanitizer,or chlorine, that you put into the water. Without any sanitizer in the water the bacteria will grow unrestricted resulting in cloudy water with plenty of food for algae to grow. The water will be very green in the spring and require much more effort and much more money spent on chemicals to resolve the problem and restore the swimming pool to a swimable condition.
Winterizing The Skimmer
Once you have the chemical balance in the water under control and have removed any organic debris or material in the swimming pool it is time to prepare to close the pool. To close the pool properly you must in drain the water down below the lowest return fitting. With the water level down this low you can manage to remove all of the water from the plumbing lines by way of blowing them out with an air blower or shop Vac vacuum set on the blow setting. The goal here is to remove the water completely to prevent any freeze expansion that could happen if there is water left in the pipes. If you do not successfully remove all of the water from the suction lines and the return lines it is very likely that you will end up with a leaking condition in your pool come springtime. It is not necessary to put anti-freeze liquid into the plumbing lines. To remove the water from the skimmer line you would set up a shop vac vacuum or air blower in the mechanical room next to the pump and he would blow the air from the pump all the way back to the swimming pool. Once you turn on the air blower the water should come flying out of the top of the skimmer however you will need to leave your air blower running for as many as 5 to 10 min. to successfully remove enough of one of the water from the skimmer that you can plug it off with a threaded plug or rubber expansion plug.
Winterizing The Returns
When winterizing the skimmer of your swimming pool it is critically important to put something down inside of the skimmer that will allow the ice that forms in there from precipitation and snow melts to not freeze and expand ultimately cracking the inside of the skimmer. The name of the product that is made for this purpose is called a gizmo which is essentially a small sealed bottle threaded down into one of the bottom ports of the skimmer. You could also use a pop bottle for example a 2 L bottle of pop partially filled with water so that the bottle will have neutral buoyancy. This allows the ice to crush inwards on this bottle as opposed to the outwards on the skimmer.
In order to properly remove all of the water from the return lines you must start at the mechanical room or pump room and blow the water back towards the pool once you have lower the water level below the return fittings. With the water level below the return fittings the water will shoot out from the returns into the swimming pool. When the water is first reaching the pool it will be hard to hold the air blower in place but after 10 to 15 seconds of running air through the system it will become a much easier to manage as the weight of the water in the lines will reduce. When you plug the returns you must do so while the air blower is still blowing so this process may require two people to complete. Be sure to plug the return that is closest to the pump room first as this will force any remaining water inside of the system to the next return line and further away. If you were to go in the opposite order and plug the return that is furthest from the pump first this would trap a pocket of water inside the plumbing lines and very likely cause a leak due to a frozen and cracked pipe. Once the skimmer and return lines have been blown out there is only two things left to consider which is covering the swimming pool and winterizing the equipment such as the pump filter and heater.
Covering The Pool
There are a few different kinds of swimming pool covers that can be used for the winter season. Of the Newer and more expensive variety are stretch safety covers which use spring compression to make the cover tight across the pool. Stretch covers require that anchors are installed into the deck all around the swimming pool and this is one of the most expensive forms of Winter covers. The other options for winter covers for a swimming pool are tarp covered whereby you would use water bags to hold a large tarp in place around the circumference of the swimming pool. The other option is what is called a lock-in the cover which can be made of vinyl or a much lighter Polyweave material. Lock-in covers connect into a separate coping track in the same way that a vinyl liner does into a coping track. Once in place you add water onto the top of the cover and this helps to hold it completely in place. This type of cover does not require any water bags or any anchors attached into the deck around the swimming pool.
Winterizing The Pump
The first thing when winterizing the equipment for your swimming pool is to remove the winterization plugs from the pump. Most swimming pool pumps have two winterization plugs usually one on the front of the wet end and one on the side where the wet end meets the motor component. When you remove these plugs this allows all the water inside of the pump and impeller compartment to drain away. No further blowing out of the pump is required as this removing of winterization plugs is all that is needed to protect your swimming pool pump for the winter. The pumps are made to stay outside for the winter season. It is not required to bring them indoors if you have removed all the water from the system. Once you have removed a winterization plug it is critically important to not lose it. The most common accepted standard is to place all of the winterization plugs from your equipment into the pump strainer basket and that is where you will store it for the off-season.
Winterizing A Sand Filter
Once you have completed the winterization of your pump you can turn your attention towards the filter. Most swimming pools in North America make use of a sand filter system. With this type of filter the first thing to do is to remove the drain plug from the bottom of the tank. It will take a few days total before the tank is drained completely. In addition to this you must be sure to set the dial of the sand filter into the winterization position to minimize any chance of breaking the filter head due to water trapped inside freezing. The filter head itself also has a pressure gauge and a backwash site glass which must be removed and then stored in the strainer basket for the pump for the season to ensure that you do not lose them.
Winterizing A Cartridge Filter
If you have a cartridge style filter for your system. You will need to open the filter and remove the four cartridges inside. Most swimming pool filters have a four cartridge system. However there are some two and three cartridge systems also. You want to remove these filters and clean them during the off-season. The way to clean the pool filter is to soak the filter in a cleaning solution that is made out of one cup of automatic dishwasher detergent to 5 gallons of water. You want to submerge the filters completely in this solution for a period of 12 to 24 hours before rinsing thoroughly. It is usually enough to just perform this maintenance task once per season. Any swimming pool with a high bather turnover rate you might want to consider doing this twice a season. As with the sand filter there is a main drain plug on the bottom of the filter tank which you will want to remove. Any pressure gauges should also be removed from the filter tank and stored in the skimmer basket for the pump.
Winterizing The Heater
The heater if you have a gas heater is the most expensive component of the plumbing system and it is very important that you winterize it properly. Failure to winterize the heater properly will almost surely results in a cracked heat exchanger which will be a very expensive repair in the spring. To properly winterize a gas heater you must remove the winterization plugs on the outside. These are usually four 9/16 inch or 1/2 inch bolts on the outside of the heater. It is very common for these bolts to become rusted over time and great care must be used to make sure that you do not strip these threads or these nuts. If your heater has a pressure switch as most older style heaters have you will need to open the heater and open the pressure switch by using two 7/16 inch combination wrenches. This will allow a small amount of water to escape from the heater. Once you have removed the winterization plugs and you have opened the pressure switch you can blow air through the plumbing system of the heater using your air blower or shop vac. This will force water out of all of the winterization ports on the heater. It is a good idea to keep the blower running for at least 5 to 10 min. to ensure that all water has been removed.
Be sure that all winterization plugs and O-rings are accounted for before closing up the system. Be sure that anything like a salt water cell or the ozone generator are removed from the system and stored indoors for the winter. Add 10L of chlorine to the pool as a final note before you finish putting the cover on and you should be good until next spring.