Pool Heat Pump Sizing Guide

Hello ePoolSupply supporters, today I wanted to talk about how to find the right heater size for your swimming pool, what kinds there are, and what to consider before committing. If you are looking to extend the fun of summer to the spring and fall seasons, then you probably want to consider a pool heater to avoid jumping into frigid temperatures. Because a pool is a large body of water sitting out in the open, it loses heat over time to the atmospheric air through evaporation.

Using a heater will bring up your temperature and maintain the desired temperature. Swimming pool heaters work by transferring heat to your pool water through a heat exchanger which allows the water to warm up by exposing the water to a source of heat as it pumps through the heater. There are many factors to consider when looking at different kinds of heaters, keep on reading to learn the different types of heaters and how to calculate to find the perfect size.

Types of Heaters

All heaters are measured in BTU which is short for British thermal units, this is a unit of measurement that measures thermal energy. One BTU represents the amount of energy needed to increase the temperature of 1 gallon of water by 1 degree Fahrenheit. The heater is responsible for warming your water so you can enjoy your pool and or spa in the off-season and the evenings. There are three types of heaters available for your pool and or spa: natural gas or propane, electric, and hybrid. Each functions a bit differently and is suited for a wide range of pool owners.

When talking about gas heaters, are commonly known as a popular choice for pool and or spa owners because of how quickly they can heat the water. The waiting time to enjoy the warmer water is virtually nonexistent because of the high output they can provide (when referring to the sap as a pool will require a little bit of wait time). These heaters are available in natural gas or propane. Propane on the other hand will need a separate propane tank whereas natural gas needs only a connection line for fuel.

Another option is a heat pump which uses electricity to efficiently move heat from the air to your pool water. The warmer air is drawn into the heater and then transferred through a heat exchanger. These heaters are ideal for spa owners in a warmer climate that’s above 40 degrees Fahrenheit because they do run depending on outside weather sources. The other heater option is a hybrid this combines the fast heating ability of a gas heater and the energy efficiency of a heat pump. This will produce more heat with less energy to minimize carbon footprint. It also has longer service life and dependable operation. A hybrid heater can operate at low air temperatures and is more efficient than a gas heater.

One of the best brands of heaters is Pentair MasterTemp Heaters and they offer all the efficiency, convenience, and reliability features you want in a pool heater, plus a lot more fast heat-up, compact design, super quiet operation, and easy-to-use. The MasterTemp High-Performance Heater has earned a reputation for being dependable, easy to use, and efficient. And now with the addition of smart connectivity and energy-saving automation, you can ensure your pool is ready whenever you are.


Check out all the heaters we sell: https://www.epoolsupply.com/collections/heaters

How to Find the Right Size Heater

As with all pool heaters, the bigger, the better. So please note, that if you go big then you are golden. A smaller pool heater won't necessarily be detrimental but you'll have to run it longer and may have problems keeping it warm. Pool heaters measure their power in BTU, so to determine the correct size of the pool heater you need a little bit of math needs to be done. The first step is to calculate your pool's surface area and all you have to do is multiply your pool length by the width. The next step is to determine your pool's average depth and how to do that is by determining the depth of the shallowest and deepest part then add those two numbers together and divide by 2. The third step is to calculate the volume of your pool in gallons, you will take the surface area and multiply it by your average depth and this will be your cubic feet to convert this into gallons all you need to do is multiply it by 7.48.

There is a lot of math to find the perfect size. If you want a quicker way to find the size you need please refer to the graphs below. Please keep in mind that more BTUs mean more power, more heat transfer, quicker results, and fewer operations time.

Things to Consider

Before choosing a pool heating solution, there are a few factors to consider to find the right size heater. One thing to consider is the climate, so if you live where it is warm primarily, then getting a heater with the recommended number of BTUs would be great. However, if you go through all 4 seasons then the bigger the better. Another thing to consider is the type of pool heater you want each type has its pros and cons so consider your budget, lifestyle, and personal preferences before committing. Also how fast you need your pool heater to work is something to keep in mind so if you use your pool frequently then consider one with a higher BTU. If you only use your pool occasionally then a heater with the recommended BTU would be the better option. Something else to consider is if you have an in-ground or above-ground pool, above-ground pools lose heat faster than in-ground pools, so you'll want to lean toward the higher end of the recommended BTU spectrum if you have an above-ground pool. One of the most important things to consider is what brand you want to go with and the quality of the heater. Always do your research before fully committing, it would be best to talk to a pool professional and see what they recommend.

To maximize your pool heating then maintaining proper pool chemistry will minimize the chance of heater damage or corrosion. Another thing to remember is if you go through all the seasons then it would be beneficial to winterize your pool equipment. Managing the run-time of your pool heater efficiency is one of the best ways to lower utility costs and keep more money in your pocket. Pool automation systems can help reduce operating costs by enabling you to set schedules and run times for your pool heating technology and equipment, so your pool is warm when you want it to be and saving you energy when you don't.

In conclusion, adding a pool heater allows you to extend your swimming season and control your pool water temperature for the perfect swimming experience. A pool heater can also be a significant investment. One of the most significant factors associated with operating your pool heater is efficiency. The more energy-efficient the pool heater, the lower the operational cost, and the less time it needs to run to deliver the same amount of heat for your pool water. If you are still unsure about anything please contact us.

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