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Common Pool Closing Mistakes

Pool Closing Tips
If you want to winterize your own swimming pool this is something that the average pool owner can accomplish. The concern is that if you make a mistake with the pool closing this could end up costing you next spring. The process of closing a pool is to protect it while it sits dormant and if you live in an area where it freezes during the off season this presents some serious concerns. Both the pool as well as the plumbing can be damaged by freezing conditions. If you do not winterize your pool correctly this is not a guarantee that your pool will be broken, but you are leaving the door open to some serious (and expensive) repairs if the worst happens. Even if you have been closing your pool for years without problems this does not mean that there isn't room for improvement with your process. From my experience as a pool and spa expert this list covers the most common areas where pool owners are likely to make a mistake.

If you need extensive instructions on how to close a swimming pool you can watch my pool winterizing series which details the entire process step by step.

How To Winterize Pool Return Lines

The return lines for the pool (where the water returns to the pool from the filtration equipment) are a very common place where a novice pool owner can make a mistake that leaves the door open for a potential failure. When winterized properly the return lines from the pool will be completely dry and plugged to prevent water from leaking back in over the winter. With no water in the pipes there is no potential for freezing to damage them. If you do not succeed in removing 100% of the water then that is all it takes for a section of the return line to crack or split when the water freezes. Moisture in the lines is not enough to cause a problem, the problem exists if there is enough water to effectively fill the pipe completely in any spot. If this area freezes the chances of developing a leak are very high. Since underground leak repair is an expensive and frustrating process in the best of times, and a total disaster in the worst of times, this is obviously something that you want to avoid. The reason why this area in particular is a major concern is that evacuating all of the water from the pipes is not exactly straight forward.

How to winterize pool returns
Most in ground swimming pools have multiple return lines, usually between 2 and 4 in total. In the equipment room there is usually only one pipe that returns to the pool. The returns are most commonly connected underground making it impossible to completely isolate each line. When a professional swimming pool service company closes a pool they would blow from the pump room location through the return lines and back to the pool. If this is all that you do then there is a very high chance that you will end up trapping some water in the lines. When you put the blower on the return line water will begin to come out of the return that is located closest to the pump room. It is important that you note which return the water comes out from first (you will need two people to accomplish this).

Once the water has almost completely stopped coming from that first return (only misting now) then you would plug it (temporarily) and the water remaining in the lines will now begin to exit from the next closest return. When the water has stopped with the second return you can plug this one as well now and continue down the chain until all of the returns have been plugged except one. When you get to the last return use your fingers to stick into the return and restrict the air flow. This will cause the velocity of the air leaving the return to increase and will help to remove the final bit of water from the lines. Once you have finished turn of the air blower, add 12 inches of foam rope to each return, and plug each return. By starting with the closest return and working the water through the system to the last return in the line this will make sure that you do not trap any water in the middle of the line somewhere.

How To Winterize A Pool Skimmer

The skimmer is one of the most likely places to have a problem with your pool if you do not winterize it correctly. Unfortunately skimmer repairs (and replacement) is an expensive process no matter what kind of swimming pool you have. In a worst case scenario a broken skimmer can require a new liner installation in vinyl pools, or tile / interior surface work in a concrete pool. In a concrete pool it is also common for the skimmer to be encased in a solid cube of concrete which makes replacement a serious project. If you have a problem with your pool skimmer and need to replace one then you can read my article on how to replace a pool skimmer which covers both vinyl pool skimmer replacement as well as concrete pool skimmer replacement.

There are quite a few different skimmer plumbing configurations and the variance in design can cause some confusion when it comes time to winterize the pool. In ground swimming pool skimmers have two ports on the bottom. Some pools will utilize both of these skimmer ports and some will not. At the very least one pipe will go directly from the skimmer port to the suction side of your pool pump. If this is all that you have then you would find that the second port in your skimmer has been permanently plugged. If this is the case then your skimmer is the easiest to winterize. Simply blow through the suction lines in front of the pump, through the lines and back to the skimmer. Since the skimmer body is filled with water the blower will struggle at first to get the water out. It will begin to roll out through the mouth of the skimmer into the pool. If your blower is strong enough then simply let it run for 5 to 10 minutes. Eventually all of the water will blow out and the skimmer will only be misting. Once you have reached this point continue to let the blower run for at least a few more minutes. The skimmer will never get 100% dry but when there is almost no water left misting out then you can turn off the blower. Add 1 liter of swimming pool antifreeze into the open skimmer port, as well as 12 inches of foam rope down into the open port. You can then screw in your gizzmo into the skimmer port. As a final step add one more liter of swimming pool antifreeze into the skimmer body itself which will help to protect against any water that finds it way into the skimmer body over the winter. Put the lid for the skimmer into a plastic bag and put it back on the skimmer securely. This will help to limit the water that is able to find its way into the skimmer. The importance of using a gizzmo in your skimmer can not be understated. I have encountered many pools that do not use any form of freeze protection inside the body of the skimmer. If you live in an area with freezing temperatures in the off season then I would certainly recommend that you use a gizzmo every year. If your skimmer does not have threaded ports to use a gizmo then a plastic pop bottle 1/3 filled with salt water with the lid screwed on tightly will work just as well.

If you have more than a single port open inside of your skimmer then there are only a few configurations that this could be. The first is that one port connects from the bottom of the skimmer directly to an equalizer port in the wall of your pool. If you have this the equalizer port would be on the wall directly below the skimmer location. If you have this then blow out the pipe, plug in the pool as well as inside the skimmer, and then blow out the skimmer line in the same fashion as described above. The most common configuration for the skimmer on modern day pools is to have the back pipe (furthest from the pool) that goes directly to the suction side of the pump, with the front port (closest to the pool) going down to the main drain in the bottom of the pool. This configuration works the same as the wall mounted equalizer except that you do not have the option to plug the pool side of the line since it is down in the main drain at the bottom of the deep end. Blow through the equalizer line in the skimmer and add as much foam rope as you can sleeve down inside. Since there is no guaranteed method to eliminate the water from this line you will be relying on the foam rope to absorb any forces from water freezing inside the line. Once you have put the foam rope in the equalizer line then you can plug it and blow out the other skimmer port that is connected to the pool pump as per the instructions above.

How To Winterize A Pool Pressure Switch

How to winterize a pool heater pressure switch
As discussed in my detailed article on how to winterize a pool heater your pool heater is the most expensive piece of equipment on your pool pad and you certainly do not want it to break due to improper winterization. Most pool owners know that in order to winterize the heater you will need to remove the drain plugs and blow air through the plumbing inlet and outlet. If you are new to closing your pool then the most likely mistake that you would make would be forgetting to open and drain the pressure switch in side the heater.

The problem with the pressure switch inside of pool heaters is that not every pool heater has one that you need to open, and the ones that do have them all have the pressure switch located in different places. Pentair notably does not require pressure switches to be open on any of their newer heaters. Hayward forced draft series heaters also do not require a pressure switch to be opened however ED2 model heaters and older H model heaters do have pressure switches located inside the service panel. Raypak and Rheem also have pressure switches that need to be opened. The good news is that winterizing the pressure switch is very easy in that all you need to do is open the pressure switch connection before you blow through the heater. Simply leave the pressure switch disconnected until spring when you put it back together. If you can locate a pressure switch then this is half the battle. Be sure to turn off the power to your heater before you attempt to disconnect the pressure switch. If you are wondering why this small switch is so important it is because they break very easily if you do not drain them and replacement heater pressure switches are very expensive, usually a few hundred dollars.

Common pool closing mistakes part 2

Things you will need to close your pool

Pool winterizing discussion

How to protect your pool from freezing

Should you drain your pool for the winter?

How to winterize a pool heater

How to have clear water when you open your pool in the spring

Swimming Pool Steve

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