How to Heat a Swimming Pool with an Air Conditioner

Using an air conditioner to heat a swimming pool may sound counter-intuitive. However, the reality is that it is possible to harness the power of your heating and air conditioning to create a comfortably warm backyard water feature.

Read on to discover the simple steps you’ll need to follow, including preparing your pool for heating, modifying the air conditioner, and ensuring safety precautions are in place. With expert guidance, you’ll soon enjoy a relaxing, heated pool in your backyard.

Can I use my air conditioner to heat my pool?

Definitely. To achieve this, you must have a specific type of air conditioner – a heat pump – which can heat and cool a space.

To heat your pool, the heat pump actively extracts warmth from the surrounding air and transfers it into the pool water. A heat exchanger, an essential component in any heating and air conditioning system, accomplishes this.

The efficiency and capacity of the heat pump present limitations when using an air conditioner to heat a swimming pool.

To determine if your air conditioner can heat your pool, you must evaluate its specifications, such as type, capacity, and efficiency. Seek advice from a heating and air conditioning company professional to assess the feasibility of using your heat pump for specific types of pools.

What are the common problems to look out for?

A few potential issues may arise when attempting to heat a swimming pool with an air conditioner. Here are some common problems and recommendations for troubleshooting and avoiding them:

Insufficient heating

If your heat pump struggles to heat your pool to the desired temperature, it may be due to an undersized unit or a decrease in outdoor air temperature. To avoid this issue, ensure your heat pump is appropriately sized for your pool and consider using a supplemental heating system in colder climates.

Inefficient heat transfer

A dirty or clogged heat exchanger can impede heat transfer and reduce the efficiency of your heating system. Regular heat exchanger maintenance and cleaning are essential to prevent this problem.

High energy consumption

While heat pumps can be an energy-efficient way to heat your pool, they can also lead to high energy bills if misused. To minimize energy consumption, use a pool cover to reduce heat loss and maintain optimal water chemistry to improve heat transfer.

Pool pump issues

The pool pump circulates water through the heat exchanger, and any problems with the pump can affect the heating process. Regular pool pump maintenance, including checking for leaks and ensuring it is running smoothly, is crucial to avoid this issue.

Steps for Heating a Swimming Pool with an Air Conditioner

Before you heat your pool, it is crucial to ensure it is adequately prepared. First, make sure to clean the pool and remove any debris. Next, check the pool’s water chemistry, which can affect heating efficiency.

The pH, chlorine, and alkalinity levels should all be balanced. Additionally, consider the types of pools that work best for this method. A backyard water feature such as a small pond or fountain is typically unsuitable for this heating system. When seeking professional advice, consult a heating and air conditioning services provider for recommendations specific to your pool.

Modification of the air conditioner for heating

Modifications are necessary to use an air conditioner for pool heating. The goal is to redirect the heat generated by the air conditioner’s condenser unit into the pool water. This may involve removing and replacing the evaporator coil with a heat exchanger designed for pool heating. You may need to consult heating and air conditioning services for assistance with this modification, as it requires specialized knowledge and tools.

Installation of the modified air conditioner

Once the air conditioner is modified, it’s time to install it near the pool. Position the unit so the heat exchanger is submerged in the pool water and the rest of the air conditioner is safe from water exposure.

Ensure the unit is level and securely fastened, as any movement could damage the heat exchanger or other components. It is also essential to consider the types of pools compatible with this installation. For proper installation, a backyard water feature may need more water volume or depth.

Operating the modified air conditioner to heat the pool

After installation, you can begin using the modified air conditioner to heat your pool. The heat generated by the condenser unit will now be transferred directly into the pool water. Monitor the temperature to ensure the unit is effectively heating the pool. Remember that the water may take some time to reach your desired temperature, especially if the pool is large.

Monitoring and maintaining the modified air conditioner and pool temperature

Regularly monitor the pool temperature and check the air conditioner for any signs of wear or damage. Clean the heat exchanger periodically to maintain efficiency and prevent debris buildup. Schedule regular HVAC services to ensure your system runs optimally.

If you have other types of pools or water features, consider having them serviced as well.

Safety Precautions

Ensure a safe pool heating experience by following electrical safety guidelines, maintaining water safety, and adhering to general precautions. Consult a heating and air conditioning professional for expert advice, use protective gear during installation, and educate users about the modified system to prevent accidents and mishaps.

Electrical safety

When working with electricity and water, prioritizing safety is crucial. Ensure all electrical connections are waterproof and follow local electrical codes. Hire a licensed electrician for any electrical work, and consult heating and air conditioning services for recommendations.

Water safety

To maintain water safety, regularly test the pool’s water chemistry and adjust as needed. Avoid using the air conditioner as a pool heater if the water contains high chemicals or debris, which can damage the heat exchanger.

General safety precautions

When operating and maintaining your modified air conditioner, follow all manufacturer guidelines and safety precautions. Keep children and pets away from the air conditioner and any electrical components. Immediately shut off the air conditioner and contact a heating and air conditioning services professional for assistance.


Heating your pool with an air conditioner is an ingenious way to repurpose energy and enhance your backyard experience. For individuals considering this option, we recommend consulting with heating and air conditioning services to ensure that your air conditioner is suitable for modification and to receive expert guidance throughout the process.

As you embark on this project, continue to explore further research and resources to refine your approach and achieve optimal results. By embracing this creative solution, you’ll contribute to a more sustainable future while creating a cozy and inviting pool retreat for all to enjoy.