Swimming Pool Blog

Pool Winterization Tips

Measuring for a Pool Safety Cover
by Rob Cox September 11, 2013

Pool Closing Tips & Tricks

Sorry, Pool Closed for WinterPool winterization is a careful chore. Do it incorrectly, and you could face expensive and frustrating freeze damage repairs next spring.

For regions with temperatures that dip below freezing for days or weeks - more than just an occasional overnight freeze, you need to winterize the pipes and equipment to protect them from freezing.

The pool, without circulation and filtration, will also need closing attention. Cleaning, chemicals and covering the pool will protect the water during winter.

Here's some Top Tips that I came up with for winterizing a pool. If you have tips, leave a comment below, or send me an email!

Lowering the Water

For solid covers, go 4 inches below the skimmer, and for mesh safety covers, go 8-12 inches below the skimmer, depending on how much winter rain and snow you receive.

To find out how much rain your city gets during winter, see this cool historical weather tool. Enter your zipcode on the first page, then select the custom tab to enter a date range.

To pump below the skimmer, close the skimmer valves, leaving the main drain open. If the drain is not operational, or if you have a side by side (2 hole) combo skimmer, use a vacuum hose / head, to draw water from the pool, connected tightly to a hose adapter screwed into the skimmer hole. For Anthony pools or old style Sylan pools that use a vertical diverter, plug the single skimmer hole with a #10 plug, to pump from main drain only.

After backwashing the filter, set Multiport valves to 'Waste' to continue pumping the pool at a higher flow rate. If you have a Cartridge or DE filter, you can open the air bleeder, and remove the filters for cleaning, while continuing to pump on the Waste setting.

Winterizing the Pipes

Lowering the water will naturally lower the water in the pipes, and in some cases, some of the water will drain out of the return lines. Air is used to force water out of the pipes, and then the empty pipes are plugged at the pool.

Once the water has been pumped below the skimmer opening, if you have separate valves, you can open the skimmer valve slowly, to suck out the line. Be quick to close the valve before air sucked in at the skimmer reaches the pool pump, so you don't lose prime.

The Mighty Vac was always my tool of choice for blowing the lines. In some cases, you can use a powerful shop vac to blow, or vacuum the water from the skimmer pipe, but need to be careful to blow out all of the water, and most cannot blow out a main drain.

If you're not sure of the success of your line blowing you can add non-toxic pool antifreeze to the pipes. For the skimmer, just pour it in. For other lines, you can use a 5 foot piece of hose, connected to a large funnel. Insert the hose through the pump or a valve, and pour in the directed amount of pool antifreeze, so that it flows into the lines (pipes).

Covering the Pool

Once the pool is clean, you should cover it as soon as possible. A clean pool will keep more of the winterizing chemicals in the water, and reward you with a faster and easier pool opening.

On a windy day, you can cover the pool immediately after cleaning the pool, leaving it open in certain areas, for access to add chemicals and plugs for the return lines or pool cleaner line. When complete, button up the pool cover.

For solid pool covers using water bags, lay them out around the pool, and drag the hose around to them. In cases where the hose is not long enough, line them up on a slight slope, insert the hose and let them fill without having to hold them.

To prevent damage to water bags, never drag the bag, or drop them from any height. To keep thirsty critters from poking holes in the bags and drinking from the fountain, set a few large bowls of water around the pool. Change the water every few weeks. Or just use Aqua Blocks.