How to choose a heat pump for a swimming pool
Short answer: A pool heat pump is selected based on the water volume, compressor type (inverter or standard), desired water temperature, and the presence of a solar cover. For a private outdoor pool measuring 6x3 m (27 m³) without a cover in Ukraine, the AstralPool AquaHeat PRO 9 kW is an inverter model designed for pools up to 50 m³.
Why do you need a heat pump and how is it better than an electric heater?
| Heating method | Seasonal consumption (27 m³) | Swimming season | Weather dependence |
|---|---|---|---|
| Electric heater 12 kW | ~15,000 kW h | 3 months | No |
| AquaHeat Compact 11.5 kW | ~3,500–4,000 kW h | 5-6 months | Partial |
| AquaHeat PRO 9 kW (inverter) | ~2,500–3,000 kW h | 6–7 months | Minimum |
Savings compared to an electric heater at a rate of 4.32 UAH/kWh — from 45,000 to 55,000 UAH per season for a 27 m³ pool. The payback period for an inverter pump is 1–2 seasons..
6 basic steps to make the right choice:
Step 1: Calculate the pool volume
Volume = length x width x average depthExample: pool 6×3 m, depth 1.5 m → 6 × 3 × 1.5 = 27 m³
When selecting a heat pump, knowing only the pool volume isn't enough. Water surface area (heat loss is significantly related to water surface area, especially due to evaporation), air temperature, desired water temperature, pool cover, and season length are also important.
Step 2: Select the power according to the coverage
The key point: The manufacturer's tables indicate the volume for the pool with coveringSolar film reduces heat loss through evaporation by 70–80%. Without a cover, a more powerful pump is needed.
| Pool volume | With cover | Without cover |
|---|---|---|
| up to 25 m³ | AquaHeat PRO 9 kW | AquaHeat PRO 9 kW |
| 25–50 m³ | AquaHeat PRO 9 kW | AquaHeat PRO 11.5 kW |
| 50–70 m³ | AquaHeat PRO 11.5 kW | AquaHeat PRO 15.5 kW |
| 70–90 m³ | AquaHeat PRO 15.5 kW | AquaHeat PRO 19.5 kW |
| from 120 m³ | AquaHeat Ultra + PRO 28,3 | AquaHeat Ultra |
Step 3: Three AstralPool AquaHeat Series – Which One is Right for You?
AstralPool offers three series of heat pumps, presented in the catalogue ModernPools:
AquaHeat Compact – for small private pools
Standard compressor (non-inverter), three power models. Suitable for pools up to 45 m³ during the warm season. COP 5.3–5.8 is a good value for a standard pump.
| Model | Power | Pool volume | COP | Voltage |
|---|---|---|---|---|
| AquaHeat Compact 8.4 kW | 8.4 kW | up to 45 m³ | 5,8 | 220V |
| AquaHeat Compact 11.5 kW | 11.5 kW | up to 60 m³ | 5,6 | 220V |
| AquaHeat Compact 15.5 kW | 15.5 kW | up to 75 m³ | 5,3 | 220V |
AquaHeat PRO — inverter models for private and commercial pools
Variable-speed inverter compressor. Smoothly adjusts power according to needs, saving up to 30% on energy compared to a Compact model. Wide range of models from 8.4 to 28.3 kW.
Key difference: The COP ranges from 13.4 to 4.95 depending on the load. When maintaining temperature (minimum load), the COP can reach 12+, representing extremely low power consumption.
The recommended choice for most residential pools.
| Model | Power | Pool volume | COP | Voltage |
|---|---|---|---|---|
| AquaHeat PRO 9 kW (AHP84) | 8.4 kW | м | 13,4 | 220V |
| AquaHeat PRO 11.5 kW (AHP115) | 11.5 kW | up to 60 m³ | 13,4 | 220V |
| AquaHeat PRO 15.5 kW (AHP155) | 15.5 kW | up to 75 m³ | 12,6 | 220V |
| AquaHeat PRO 19.5 kW (AHP195) | 19.5 kW | up to 95 m³ | 12,4 | 220V |
| AquaHeat PRO 24.2 kW (AHP242) | 24.2 kW | up to 120 m³ | 12,4 | 220V |
| AquaHeat PRO 28.3 kW (AHP283) | 28.3 kW | up to 170 m³ | 12,4 | 220V |
AquaHeat Ultra — for large pools from 120 m³ (three-phase)
Requires connection to a three-phase 380V network. Suitable for hotels, water parks, and sports complexes.
| Model | Power | Pool volume | COP | Voltage |
|---|---|---|---|---|
| AquaHeat Ultra 29.5 kW (AHU295) | 29.5 kW | up to 170 m³ | 12,7 | 380V |
| AquaHeat Ultra 34.7 kW (AHU347) | 34.7 kW | up to 200 m³ | 12,5 | 380V |
How to read COP range: 12.7 is the COP at minimum power (temperature maintenance, pump "breathing"), 4.95 is the COP at maximum power (heating from zero). In real-world use, the pump operates at partial load most of the time, so the average COP over the season is significantly higher than 4.95.
Step 4: Inverter (PRO) or Standard (Compact)?
| Parameter | AquaHeat Compact | AquaHeat PRO (inverter) |
|---|---|---|
| Operating principle | Turns on/off completely | Smoothly regulates power |
| COP at full load | 5,3–5,8 | 4,95 |
| COP at part load | 5.3–5.8 (does not change) | up to 13.4 |
| Average COP for the season | ~5,7 | ~8–10 (mostly partial load) |
| Accuracy of temperature maintenance | ±2–3°C | Constant, automatic |
| Energy saving | Basic | +30% vs Compact |
| Power range | Fixed | from 4.6 kW to the maximum model |
| Price | Lower | 10-30% more expensive |
| Recommended for | Seasonal use | Permanent / Off-season |
Important: COP at full load is formally higher for Compact than for PRO, but this is the maximum figure under certain conditions. The PRO inverter pump is more economical in actual operation due to smooth regulation - it does not waste energy on frequent starts and stops. Catalog of inverter heat pumps for swimming pools.
Step 5: Technical requirements are the same for all series
- Operating range of air temperatures: +7°C to +43°C
- Housing protection: IPX4 (suitable for outdoor installation)
- Heat exchanger: titanium - resistant to chlorinated and salt water
- Connection diameter: 50 mm (for all models)
- Manufacturer's warranty: 3 years
- Service life: 10-15 years
Step 6: Location of the heat pump
- At least 50 cm of free space on all sides for air circulation
- Do not install in closed niches — performance will decrease
- Connection to the circuit: after the filter, before the disinfection station
- Hose diameter: 50 mm (included in standard connections)
- При использовании соляного электролиза (хлоргенератора): насос с титановым теплообменником — обязателен. Все AquaHeat соответствуют этому требованию.
ModernPools Engineer Tip:
For a standard 6x3 m private pool in Ukraine (without regular professional service), we recommend the AquaHeat PRO 9 kW (AHP84)—it offers the optimal balance of price, power, and efficiency. The pump is designed for volumes up to 50 m³, providing ample power for uncovered operation and in cool weather. The actual average COP over the season (taking into account partial load operation most of the time) is approximately 8–10, which, with eight hours of operation and a rate of 4.32 UAH/kW, translates to approximately 15–25 UAH per day for temperature maintenance. This is 10–12 times less than with an electric heater.
If you want to extend the season as much as possible (March–November) and don’t have a cover, consider the AquaHeat PRO 11.5 kW (AHP115).
Frequently Asked Questions (FAQ)
The AstralPool AquaHeat PRO 9 kW (AHP84) is designed for up to 50 m³ of capacity, providing ample headroom for uncovered operation. If you have a solar film, even the AquaHeat Compact 8.4 kW is sufficient. The price of the PRO 9 kW at ModernPools in 2026 is UAH 81,855.
For a 30 m³ pool with a cover, the AstralPool AquaHeat PRO 9 kW (AHP84) is suitable (rated for up to 50 m³). For a pool without a cover, or if you want to operate from April to October, choose the AquaHeat PRO 11.5 kW (AHP115). Opt for the PRO model rather than the Compact: the inverter compressor is significantly more energy-efficient during prolonged use.
The Compact is a standard compressor (completely on/off), while the PRO is an inverter compressor (smoothly adjusts power). The PRO saves up to 30% energy over long-term operation and operates quieter at partial load. The price difference in 2026 is 8,000–12,000 UAH. With regular use, the investment pays for itself within one season.
The actual (not rated) minimum operating temperature for all AquaHeat series is +7°C. Below this temperature, performance drops sharply, and it is recommended to turn off the pump. For winter operation (below 0°C), models from other series are required; AquaHeat is not designed for winter use.
Yes, a bypass is recommended - it allows you to turn off the pump for maintenance or conservation without stopping the filtration systemsA bypass kit for a diameter of 50 mm is sold separately.
Install the pump in the circuit before chlorine generator - salt water without active chlorine has a much gentler effect on the titanium heat exchanger
The minimum actual operating temperature for AquaHeat is +7°C. Before winterizing the pool, the pump must be completely shut off, and the water purged from the heat exchanger or drained via the drain port. The outdoor unit should be covered with the included winter cover. The pump must not be left with water in the heat exchanger during freezing temperatures, as freezing will damage the internal components.
For a 27 m³ pool with an initial water temperature of +15°C and an AquaHeat PRO 9 kW pump (actual output at an air temperature of +15°C is ≈ 8 kW): heating 1 m³ by 1°C requires 1.16 kWh. A 13°C rise × 27 m³ × 1.16 / 8 kW ≈ 51 hours of continuous operation, which translates to 6–7 days based on 8 hours of operation per day. In practice, with solar heating and a solar cover, this takes 3–5 days.
The ModernPools catalog offers an official 3-year warranty, delivery throughout Ukraine, and a free power calculation for your pool. See the full selection: pool heat pumps.
The full range of AquaHeat Compact, PRO and Ultra series, as well as such popular brands as: EVO, Fairland, Aquaviva, Aquajoy with prices, availability and the ability to compare models by characteristics - in the catalog heat pumps for swimming pools from ModernPools. Delivery throughout Ukraine, free power calculation for your space – submit a request.
And in this section you can read more information about our pool heat pumps, to finally decide on the purchase parameters.
Any more questions? We'll be happy to answer them!