To size a pool heater properly, calculate your pool's surface area, determine the required temperature rise, and select a heater output—measured in British Thermal Units (BTUs)—that heats your pool at your desired speed.
For a 10,000-gallon pool, the ideal heater size depends on the type of heater and your climate.
Or approximately 100K BTU's for every 10,000 gallons of pool water. For inground pools less than 20,000 gallons, small gas heaters like the Raypak 206K BTU output are suitable. Pools up to 30,000 gallons should look at the Pentair 300K BTU or higher, and pools over 50,000 gallons should look at the Hayward 500K BTU.
Electric heat pumps are generally cheaper to run, while gas heaters are cheaper to buy and install. The best choice depends on how often you swim and your local climate.
Heating a 20,000-gallon pool by 10∘F10 raised to the composed with power F10∘F to 15∘F15 raised to the composed with power F15∘F generally takes 8 to 48 hours, depending on your heater type, current weather, and whether you use a pool cover.
The cost of propane is roughly $3.00 per gallon, and a 300K BTU propane heater uses 3 gallons of propane each hour to heat a standard 15,000–20,000 gallon pool 2–3ºF per hour. This means an average 300K BTU pool heater will cost anywhere from $6.00 to $8.00 per hour to heat your pool.
Is it better to oversize a pool heat pump? Yes. If you're between sizes, a slightly larger unit usually heats faster and runs fewer hours to hold temperature. It also performs better in cooler or windier conditions.
This may be one of the most simple but clever ways to heat your pool. Simply purchase a black garden hose and connect it to the outside water spigot. Ensure your hose is in direct sunlight, wrapped in a coil shape to maximize its surface area (while still reaching your spigot and pool).
A 40×20 foot rectangular pool holds roughly 21,000 to 30,000 gallons, depending on the average depth.
For concrete or gunite pools, the shell is often the single most expensive component. Furthermore, it requires extensive engineering and highly specialized labor.
That said, a 100-gallon propane tank would last around 25 hours for a 400,000 BTU heater, and a 250-gallon tank would last around 63 hours. However, this could be impacted by the factors mentioned above, and what power level your propane pool heater is on.
The cheapest way to heat a pool is by maximizing free solar energy. This means covering your pool to stop heat loss through evaporation and using solar heating mats or rings to capture the sun's warmth.
Instead of generating heat by itself, it sucks in the heat from the ambient air and transfers this heat to the water in the swimming pool. On average, an electric heat pump can take up to 12-48 hours to heat up the water in your swimming pool, up to 28 degrees.
If you choose a heater that's too small, you'll likely find that it simply can't keep up, leaving you with less-than-ideal water temperatures. On the other hand, bigger isn't always better. A heater that is too large for your needs will burn unnecessary energy, which can get expensive.
The most efficient pool heating method is a solar pool heater, which uses free energy from the sun. However, for dependable, on-demand heating, pool heat pumps are the most energy-efficient mechanical option, while gas heaters are the most efficient for rapid, high-temperature heating.
Here are three signs your heat pump may be too large for your home:
Here's the deal: A typical electric pool heater uses between 5,000 to 15,000 watts per hour. Let's break this down into real money: If you run a 5,000-watt heater for 8 hours, that's 40 kWh per day. At the U.S. average rate of $0.14 per kWh, you're looking at about $5.60 daily just for heating.
Gas pool heaters cost less upfront ($1,500–$4,000) but have high monthly operating bills ($200–$500+). Electric heat pumps cost more upfront ($2,500–$6,000) but offer much lower monthly operating costs ($100–$200), making them highly cost-effective over their lifespan.
Heating a 15,000-gallon pool typically takes 8 to 48 hours to raise the temperature by 10∘F10 raised to the composed with power F10∘F to 15∘F15 raised to the composed with power F15∘F. The exact time depends heavily on your heating method, whether you use a pool cover, and the outside temperature.
The Most Efficient Heating Schedule for Your Pool
As a rule of thumb, early morning or during off-peak electricity hours (often overnight) is the most cost-effective time to heat your pool. If you're using an electric heat pump or resistance heater, you should be scheduling your heating.
For most customers, we recommend turning on your furnace when the weather is consistently below 18° Celsius, which usually happens to be around the end of September, or early October. Some homeowners try to put off turning on their furnace as long as they can to save money, which is okay if you're healthy adults.
Pool size – Larger pools require more gallons or truckloads of water, increasing costs. Fill method – Using a garden hose costs $40 to $200 while hiring a water delivery service costs $300 to $2,000 to fill a 10,000 to 20,000-gallon pool.