Even though San Diego has a typically warm climate throughout the year, it's inevitable that temperatures will drop in the beginning weeks of spring. The cooler weather could mean less swimming, unless you decide to purchase a heat pump to keep your swimming pool active all year long.

There are multiple options available for owners to choose from depending on factors such as cost, maintenance and even personal preference. Here's why you should choose a heat pump to warm your pool water.

How does it work?
Generally, it's much easier to move or transfer heat than to generate it, which is the principle that most heat pumps follow in warming up pools. This equipment uses electricity to move heat from one place to another, rather than generating it directly like a gas heater.

As the water is circulated by the pool pump, it passes through a filter and the heat pump heater. Inside, there's a fan that draws in air from the outside and pushes it over an evaporator coil. Liquid refrigerant inside the coil becomes a hot gas as it absorbs heat from the outside air, and then passes through the condenser. The heat is then transferred from the gas into the cooler water that's circulating through the pump. The now-warmed up water is returned to the pool and the hot gas goes back through the condenser coil, turns back into liquid and begins the whole process over again.

These kinds of pumps work most efficiently when the outside temperature remains above 45 to 50 degrees. The cooler air they draw in, the more energy they use. Thankfully, the temperatures in the San Diego area are perfect for this kind of heating system.

How efficient is it?
According to Top Pool Heaters, the efficiency of heat pumps is measured by their coefficient of performance, or COP. This formula calculates how many units of heat energy are produced compared to each unit of electricity used to power the pump. The best part about heat pumps is that because they don't actually generate heat, the amount of energy being produced is far greater than the energy being used. This makes them much cheaper and more energy efficient than gas heaters.

Because choosing a pump can be determined by many factors, you should talk to your San Diego pool service professionals, who possess the expert knowledge to properly advise you on a purchase.