When your water sits all winter with no circulation, that stagnant water can be doing damage to the pool surface. Usually calcium hardness levels are not high enough to withstand the cold winter water, causing the LSI of your pool water to become corrosive. We've seen some pools take as little as $50 and as high $600 in chemicals just to get the pool water balanced for swim season; of course, this is all dependant on the chemical needs and how many gallons are in the vessel. 

In addition to the water quality, another factor to consider is the equipment. Pool equipment, similar to cars, is made to be used. There are dozens of gaskets and o-rings on the pool equipment that need to be lubricated, or keep water moving over them as the housing(s) expand and contract to prevent them from drying out and cracking. We've seen homeowners open their pool in April to green water, plus hundreds in repairs because of the pool being "closed" for the winter months.

What about the cost of running your pump all year? With new variable speed motors available on the market, you can set that pump to run on lower RPMs and circulate water without worry of it freezing and breaking pipes, and you can still have chemicals balanced weekly through the winter to ensure that the water quality stays good all year round. In the long run, this could end up saving you a lot more money and hassle.