Which capacity do you need?
A compressor label in HP is not a complete sizing calculation. Record tub volume in litres, starting and target water temperatures, hours of use, shade and the number of daily users. Ask for cooling capacity at those conditions: a rating measured with warmer water cannot establish performance at your target temperature.
Check the connections before buying
Match inlet and outlet size, hose length, required flow and pump arrangement. Some units include a circulation pump and filter; others need external components. Confirm these as one working system rather than choosing each part independently. Leave the manufacturer’s required ventilation space around the condenser.
A practical sizing example
Cooling 300 litres by 15°C removes approximately 5.2 kWh of heat: 300 × 4.186 × 15 ÷ 3600. At a constant net cooling output of 1 kW, that is at least 5.2 hours before accounting for heat entering from the room, tub and users. This is a planning example, not a promised cooldown time or electricity consumption.
What to include in your enquiry
Send the city, tub volume, indoor or outdoor location, desired temperature and a photo of the connection ports. For a gym or hotel, add the expected number of users and operating hours. This makes it possible to compare suitable options and the complete installation budget.
