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Pool Heat Pump Sizing Guide: What size do I need?

Understanding Heat Pump Sizing for Your Pool: Finding the Right Fit

Are you considering investing in a pool heat pump but feeling overwhelmed by the options available? Choosing the right size of heat pump is crucial to efficiently heat your pool while minimizing energy costs. In this guide, we'll help you choose the right size of pool heat pump for your needs by considering important factors.

Understanding Pool Heat Pump Sizing

Before diving into the sizing process, it's essential to grasp the basics of how pool heat pumps work. These devices take heat from the air and put it in the pool water, making it warmer for swimming. The effectiveness of a heat pump depends on its size, measured in BTUs (British Thermal Units) per hour.

Factors to Consider

Pool Size: The size of your pool primarily determines the size of the heat pump required. Larger pools require more heating power to raise the temperature effectively. Measure the surface area and volume of your pool accurately to determine the appropriate size.

Pool Shape: Identifying the shape (e.g., rectangular, oval, kidney-shaped) helps us utilize the appropriate formula for accurate calculations.

Dimensions: Please provide the length, width, and depth of your pool, specified in feet or meters.

Average Depth (Optional): If your pool features varying depths, an average depth measurement suffices for estimation purposes.

Water Features: Consideration of water features such as infinity edges, waterfalls, jets, or any other special features within the pool is essential for selecting the appropriate size. Kindly inform us of any such features present.

Once we have this information, we can calculate your pool volume and advise you on selecting the suitable pool heat pump size. Here are formulas commonly used for calculating the volumes of various pool shapes:

Rectangular Pool: Volume = Length x Width x Depth

Oval Pool: Volume = (Length x Width x Depth) x 0.55

Circular Pool: Volume = (π x Radius² x Depth)

Kidney-Shaped Pool: Divide the pool into sections (rectangular, triangular, etc.), calculate the volume of each section separately, and then sum up the volumes of all sections to determine the total pool volume.

COP Rating: The Coefficient of Performance (COP) is a vital indicator used to gauge the effectiveness of a pool heat pump. It represents a proportion between the energy input (electricity) and energy output (Heat/Cool). It shows how efficiently a heat pump converts electricity into heat or cool air. This efficiency depends on the setting. 

InverEco operates on the principle of low-speed performance, boasting a remarkable COP of up to 11.6 when running at just 20% capacity. Similarly, InverTITAN follows suit, leveraging low-speed operation to achieve an impressive COP of up to 14.6 at the same 20% capacity. Meanwhile, the InverELITE V2 stands out with its COP of 15.2 during low-speed operation, ensuring efficient maintenance of pool temperature. This translates to an impressive heat output of 150,000 BTUs for every 10,000 BTUs consumed.

Climate: The climate of your location plays a significant role in determining the heat pump size. Warmer climates typically require less heating power compared to colder regions. Consider the average temperature during the coldest months to ensure the heat pump can maintain the desired water temperature.

Desired Temperature: Determine the temperature at which you want to maintain your pool water. If you prefer warmer water or would like to extend your swimming time, you will need a larger heat pump. This will help maintain the pool at the temperature you desire.

To determine the required temperature increase, subtract the average air temperature during your coldest month of pool usage from your desired swimming temperature. This temperature difference represents the target increase that your heat pump needs to achieve. When considering heating speed, it's crucial to strike a balance. An undersized heat pump may struggle to maintain the desired temperature, leading to inefficiency, while an oversized one can be both inefficient and costly to operate. Opt for a heat pump capable of raising the temperature by approximately 0.20-0.25°C per hour to ensure optimal performance and energy efficiency.  

Usage Patterns: Consider how often you'll be using your pool and for how long. If you use your pool frequently or year-round, you'll need a more powerful heat pump to handle the continuous demand for heating.

Insulation and Cover: Insulating your pool and using a cover can help keep the water warm for longer. Well-insulated pools with covers require less heating power, allowing you to choose a smaller heat pump.

Discover additional insights by reading pool heating options guide by accessing this helpful article:

Sizing Calculation

Once you've gathered the necessary information, you can use a sizing calculator provided by manufacturers or consult with a pool heating specialist to determine the appropriate size for your pool. These calculations take into account factors such as pool size, desired temperature, climate, and efficiency ratings of the heat pump.

Madimack provides pool heat pump sizing calculator for you to make the right decision for your pool. Use our pool heat pump calculator to see costs, heater size, dimensions, and space needed for your pool.

Pool Heat Pump Calculator:

Benefits of Proper Sizing

Choosing the right size heat pump offers several benefits:

  1. Optimal Efficiency: A properly sized heat pump ensures that it operates at its peak efficiency level. If the heat pump is too small, it may struggle to heat the pool efficiently, leading to increased energy consumption and higher operating costs. Conversely, if it's too large, it may cycle on and off frequently, leading to unnecessary wear and tear and decreased efficiency.

  2. Cost Savings: By selecting the right size heat pump for your pool, you can avoid overspending on a larger unit that consumes more energy than necessary. A properly sized heat pump will provide the required heating capacity without wasting energy, resulting in lower utility bills over time.

  3. Faster Heating: A correctly sized heat pump can heat your pool water more quickly to the desired temperature. This is especially important if you use your pool frequently or if you need to heat it up for special occasions or events.

  4. Extended Lifespan: Operating a heat pump within its recommended capacity helps to prolong its lifespan. Avoiding overworking the unit by selecting the appropriate size ensures that it operates efficiently and experiences less wear and tear over time.

  5. Consistent Temperature Control: A properly sized heat pump maintains consistent water temperature throughout the pool, providing a comfortable swimming environment. This consistency enhances the overall enjoyment of your pool and ensures that it remains usable even during cooler weather.

  6. Environmental Benefits: Using a correctly sized heat pump reduces energy consumption and greenhouse gas emissions compared to oversized units. By maximizing energy efficiency, you can minimize your carbon footprint and contribute to environmental conservation efforts.

  7. Reduced Maintenance: A heat pump that is sized appropriately for your pool experiences less strain and requires less frequent maintenance. This can save you time and money on upkeep and repairs over the lifespan of the system.

Overall, choosing the right size pool heat pump is essential for maximizing energy efficiency, reducing operating costs, and ensuring optimal performance and comfort for your swimming pool.

Heating Comparison All territories



  • Seeking guidance from a certified pool expert is strongly advised. They can offer personalized recommendations tailored to your pool's size, local climate, and usage habits. These professionals can also consider other factors such as pool covers, solar panels, and insulation, all of which have a substantial impact on determining the appropriate heat pump specifications. Contact us:
  • Opting for an undersized heat pump can lead to difficulties in maintaining your preferred temperature, resulting in inefficiency and higher operational expenses. Select a model that aligns with both your requirements and budget.
  • Ensuring you invest in a heat pump of the correct size guarantees peak performance, energy efficiency, and an enjoyable swimming environment.

Our product review statistics showcase the outstanding quality of our offerings. Click the link to see them for yourself.

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Buying a pool heat pump is important. Picking the right size is key for best performance and saving energy.

When choosing a heat pump for your pool, consider the size of your pool. Also, think about the weather in your area and your preferred swimming temperature. Additionally, take into account how frequently you use your pool.

If you're unsure about sizing, don't hesitate to seek guidance from pool heating experts to make an informed decision. With the right-sized heat pump, you can enjoy your pool comfortably year-round while minimizing energy costs.

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