Pool Heaters – Should I get One? What Kind Should I Get?

by Frank Kearney

Wilmington Pool builder

One thing about building Pools in Wilmington, we have enough sunny weather that a pool heater can often give you better use of your pool. There are a few questions that should be considered first though, before you decide to have a heater installed.

Usually when people discuss a heater, they have a vision of using the pool all year. That is certainly possible, but consider that when the outside temperature is 40 degrees, even though the pool water is 85 degrees, with the ambient temperature so cold, you won’t want to be in the pool. So why do you need a pool heater?

This past weekend the forecast for Sunday was sunny, but the pool water was still cool. We turned on the heater Saturday night and by Sunday moring the water was a warm 88 degrees and we had a wonderful time hanging out by the pool. Sunday night we turned off the heater, closed the cover and we will be ready for the next warm weekend.

In our case we have a heat pump, but with a gas heater the results would be the same. Pool heaters will help you use the pool in those early spring weekends and late fall weekends when the water is cool but the days are warm.

The important thing to note here is the pool cover. We have an automatic cover, but a good solar cover will work well also. Solar covers are inexpensive and very good at heating a pool and keeping a pool warm overnight. You will lose your heat overnight unless you have something keeping the heat in the water. A solar cover, or automatic cover, or a manually operated cover, will keep the heat in long enough for the heater to do its job.

Gas heaters, more so than heat pumps, will give you instant heat. The advantage to a gas heater is that it is very fast and heats the water quickly. Depending on the size of the heater and the amount of water, it should be no problem to raise the water temperature ten degrees without too much trouble. Gas heaters give instant heat and a lot of it, but they are expensive to operate as propane and natural gas prices can often be very high. As long as you aren’t heating the pool 24/7, a good gas heater will serve you well. If you just want to take the edge of the cold off your pool, nothing beats a good gas heater. Also the difference in price between a medium sized gas heater and the largest is usually not very much.

Heat pumps heat over time, and if you do not have a cover on your pool, your heat pump will be working very hard to keep the water warm. If you allot enough time, and if the air is warm, a heat pump will get you ready for the weekend, and at a lot less cost, but it will be working every minute to get the temperatures up. Again, a pool cover will increase the efficiency of the heater. Heat pumps cost more to buy, but their operating costs are a lot less. If you are able to cover your pool, a heat pump is very efficient and will last for many years.

Electric heaters, are very expensive to operate, and unless the pool is very small and covered, an electric heater will not be able to heat the water. I do not recommend an electric heater except in very unusual circumstances and with a very small pool.

Recently we have seen a big increase in demand for solar heaters. This will involve a professional solar heating installer, but if you have the right location for your pool, and room for the heating panels, this is a very effective way to heat your pool. Although the operational costs of a solar pool heater are certainly lower, the cost of the equipment and installation is comparable to most heat pumps.

Finally remember that a heater is something that can be installed after the fact. We have put heaters on pools that were over ten years old. We often recommend that if you are not certain you will need or use a heater, then just delay the job until you have had time to evaluate your needs. Very often a solar cover will heat your pool enough so that you can enjoy those warm spring weekends, especially if your needs for pool heat are not as high as others. If you need your water heated into the 90’s, a cover and a pool heater are a must.