Swimming Pool Heat Pump Installations

A pool air source heat pump takes heat from the outside air and transfers it into your pool water through a heat exchanger. It uses electricity to run a compressor and fan, but it typically produces more heat energy than the electricity it consumes, making it an efficient way to heat a pool.

In many cases, yes—especially for outdoor pools during the season. Heat pumps are usually more efficient for maintaining temperature, while boilers can be better for rapid temperature increases. The best option depends on your pool size, target temperature, usage pattern, and your energy tariffs.

Sizing depends on:

• Pool volume and surface area
   
• Whether you use a cover (huge factor)
   
• Desired swimming season (summer-only vs spring/autumn)
   
• Location and exposure (wind, shade)
   
• Target temperature and warm-up time expectations
  The right size is crucial—undersizing leads to slow heating and high run times; oversizing can cause short cycling if not designed correctly.

It varies with weather and heat loss. As a rough guide, a correctly sized heat pump might raise temperature by 1–2°C per day in good conditions, but this can be faster or slower depending on pool cover use, air temperature, wind, and starting water temperature.

Pool heat pumps work best in mild conditions and become less efficient as air temperature drops. Many units can operate at lower ambient temperatures, but output reduces. For extended-season use, correct sizing and a good cover become even more important.

Strongly recommended. Most heat loss happens at the water surface, especially overnight. A cover (solar, insulated, or slatted) can dramatically reduce heat loss and running costs, and it helps your heat pump maintain temperature more easily.

Most domestic outdoor pools are comfortable around 26–29°C, depending on preference and usage (children often prefer warmer). Higher temperatures increase heat loss and running costs, so we help you balance comfort and efficiency.pump maintain temperature more easily.

Heat pumps need good airflow. They should be installed outdoors with:

• Clear space around the unit (for intake/discharge airflow)
   
• A solid, level base
   
• Consideration for noise and neighbours
   
• Good drainage for condensate
  We’ll recommend the best location during the survey.

• Modern units are generally quiet, but noise levels vary by model and installation position. Correct placement, vibration management, and airflow clearance all help. If you’re concerned, we’ll factor noise into the specification. 
• A solid, level base
   
• Consideration for noise and neighbours
   
• Good drainage for condensate
  We’ll recommend the best location during the survey.

In most cases, yes. A bypass allows accurate flow through the heat pump and helps protect the unit. It also makes commissioning and ongoing adjustments easier.

Yes—most installs are retrofits. We connect the heat pump into the circulation system (usually after filtration) and set up a bypass to control flow. We’ll check pipe sizes, pump capacity, electrics, and plant room layout first.

Often it will, but not always. Heat pumps need a minimum flow rate. If your pump is underpowered or your pipework is restrictive, performance can suffer. We check this and recommend upgrades only if needed.

Many pool heat pumps are compatible with saltwater systems, but it depends on the heat exchanger and manufacturer specification. Titanium heat exchangers are commonly recommended for saltwater environments. We’ll specify the right unit for your water type.

• On/off units run at fixed output when heating is needed.
   
• Inverter units modulate output to match demand, often running more steadily and efficiently, with quieter operation at lower speeds.
  Inverter models can be a better choice for temperature stability and efficiency, especially for longer seasons.

Running cost depends on:

• Heat pump efficiency (COP)
   
• Electricity tariff
   
• Outdoor temperature
   
• Pool heat loss (cover use is key)
   
• Set temperature
  We can give realistic guidance after assessing your pool, expected season, and heat retention.

Yes. Like any mechanical system, periodic servicing helps maintain performance and reliability. Servicing typically includes checking airflow, coil condition, electrics, refrigerant circuit indicators, water connections, and controls.

Common helpful checks:

• Keep the coil clear of leaves and debris
   
• Ensure airflow isn’t blocked
   
• Keep the area around the unit tidy
   
• Maintain proper pool water chemistry (important for all equipment)
   
• Use a cover to reduce heat loss
  We’ll provide simple handover guidance after commissioning.

Yes, but indoor pools often have additional considerations: evaporation control, ventilation, and humidity management. Heat pumps can be part of the system, but many indoor pools also need dehumidification and air handling

Sometimes, but it requires careful design and controls because pools and spas have different temperature demands. We can advise on the most practical approach for your setup.

We typically supply and install so we can ensure the specification is correct and the warranty/support route is clear. If you already have a unit, we can advise whether installation-only is suitable once we’ve checked compatibility and documentation.

Many domestic retrofits can be completed within 1 day, but it depends on:

• Pipework run length and complexity
   
• Electrical works required
   
• Base preparation and access
   
• Plant room alterations
  We’ll confirm timescales after the survey.

Helpful details include:

• Pool dimensions (length, width, average depth) or volume
   
• Indoor/outdoor and location (postcode)
   
• Desired season and target temperature
   
• Whether you use a cover (and what type)
   
• Photos of the plant room and proposed heat pump location
  If you don’t have all of this, we can still start with a quick call.

• Warmpools installs across Essex, London, Kent, Surrey, Suffolk, Sussex, Hertfordshire and most of the south east. If you’re just outside these areas, contact us—depending on the project we may be able to help.Whether you use a cover (and what type)
   
• Photos of the plant room and proposed heat pump location
  If you don’t have all of this, we can still start with a quick call.

The most common issues are:

• Choosing a unit that’s too small
   
• Not using a pool cover
   
• Poor placement with restricted airflow
   
• Incorrect flow rates/no bypass
  A properly designed and commissioned install avoids these pitfalls.
   

Send us your pool dimensions, postcode, and a couple of photos of your plant room/outdoor area (if available). We’ll recommend the right heat pump size and provide a clear quote for supply, installation and commissioning.