Yes — pool heating is the heat pump's best-case application. Because pool water needs only 26–30 °C, the temperature lift from outdoor air is tiny and dedicated pool heat pumps reach COP 5–7: one kWh of electricity delivers 5–7 kWh of heat. A covered 32–40 m³ garden pool in central Europe typically needs a 9–13 kW unit for a May–September season.
Why are pool heat pumps so efficient?
Heat pump efficiency depends on the temperature lift between source and target. Space heating lifts winter air to 35–55 °C water; a pool asks only for 26–30 °C from mild spring-to-autumn air — often a lift of just 10–15 K. That is why pool units achieve a COP of 5–7 where the same hardware doing radiator duty manages 3–4. An inverter compressor amplifies the advantage by trickling heat in continuously at low fan and compressor speed — quieter and more efficient than stop-start operation. One caveat rules them all: evaporation is by far the largest source of an outdoor pool's heat loss (US DOE), so a pool cover is not an accessory but half the heating system — covering the water cuts heating demand by 50–70%.
What size pool heat pump do you need?
Sizing follows surface area, season and cover discipline more than volume alone. Central European guide values for an outdoor pool at 27 °C:
| Pool (surface / volume) | With cover, May–Sept | Without cover, May–Sept | Extended season (Apr–Oct) |
|---|---|---|---|
| 6 × 3 m / ≈25 m³ | 5–7 kW | 9–11 kW | 9–13 kW (covered) |
| 8 × 4 m / ≈40 m³ | 9–13 kW | 15–18 kW | 13–17 kW (covered) |
| 10 × 5 m / ≈65 m³ | 13–17 kW | 21–26 kW | 17–24 kW (covered) |
Southern climates sit at the lower bounds, windy or shaded sites at the upper. Undersizing shows up as a pool that takes a week to recover after a cold spell; gross oversizing mainly wastes capital, since the pool itself is an enormous thermal buffer.
Can your house heat pump also heat the pool?
Yes, if it has spare capacity outside the heating season. The pool circuit connects through a corrosion-proof intermediate heat exchanger — titanium or high-grade stainless steel, because chlorinated water attacks standard materials — with the controller giving priority to domestic hot water and space heating. Proper hydraulic separation keeps pool duty from disturbing house circuits. The match is seasonal by nature: a space-heating unit idles exactly when the pool wants heat, so summer pool duty adds run hours at the machine's highest-COP operating point.
Is solar thermal or a heat pump better for pool heating?
They solve the same problem from opposite ends, and the strongest systems combine them. Solar collectors deliver pool-grade heat at zero marginal cost precisely in the sunny months when the pool is open — Solimpeks Wunder flat-plate collectors have served pool and DHW duty since the company began manufacturing in Konya in 2001 — while the heat pump guarantees target temperature through cloudy weeks and shoulder months. A solar controller simply runs the free source first and the compressor second. For sizing the solar side, the logic mirrors how many solar collectors do I need; as a guide, collector area of 50–80% of the pool surface carries a covered southern-European pool with minimal electrical top-up.
How much does pool heating cost to run?
A covered 8 × 4 m pool in central Europe needs roughly 3,000–5,000 kWh of heat for a May–September season. At COP 5 that is 600–1,000 kWh of electricity — about €170–290 at the EU-average household price of €0.29/kWh (Eurostat, H2 2025). Leave the same pool uncovered and demand can double or triple, which restates the economics: the cover saves more money than any equipment upgrade, and solar input can push the residual electrical cost toward zero.
Frequently asked questions
What temperature can a heat pump keep a pool at?
Residential pool heat pumps comfortably hold 26–30 °C through the season and 32–35 °C for spas and therapy pools. Higher setpoints raise energy demand steeply — each extra degree adds roughly 5–10% to seasonal consumption.
How long does a heat pump take to heat a pool initially?
First heating from about 15 °C to 27 °C takes 2–5 days depending on unit size, cover use and weather — a 40 m³ pool needs roughly 560 kWh of heat for that 12 K rise. After that the unit only replaces daily losses.
Can I run a pool heat pump in winter?
Dedicated pool units are built for air above roughly 5–10 °C; year-round pools need a low-ambient model with defrost capability, and consumption rises sharply in cold months. For summer-season pools, winterising the circuit is the economic choice.
Why does a pool heat pump need a titanium heat exchanger?
Chlorine and salt-electrolysis water corrode copper and standard stainless steel. Titanium exchangers are immune to both, which is why every quality pool unit or intermediate exchanger uses them — never pipe pool water directly through a space-heating condenser.