| Cooling Capacity | Select capacity according to spa volume, desired pull-down time, ambient temperature, insulation, and cover usage. A common small-to-medium spa range is approximately 2–10 kW of cooling capacity. | An undersized unit may run continuously without reaching the target temperature, while an oversized unit can increase purchase and operating costs. | Request capacity data at the actual entering-water temperature, leaving-water temperature, and outdoor ambient condition—not only a nominal rating. |
| Water Temperature Range | A practical chilled-water operating range is commonly around 7–35°C, depending on the system design and control settings. | The usable range determines whether the chiller can support cooling, recovery, and seasonal operating requirements. | Check the minimum and maximum setpoints, anti-freeze protection, sensor accuracy, and the manufacturer’s operating limits. |
| Energy Efficiency | Compare COP or EER under identical test conditions. For water-cooled or air-cooled systems, efficiency varies significantly with water temperature and ambient conditions. | Electricity consumption is often the largest long-term operating expense for a commercial or residential spa installation. | Ask for rated input power, cooling output, COP or EER, and test conditions. Avoid comparing efficiency figures measured at different temperatures. |
| Compressor Type | Scroll compressors are commonly used for stable performance and low vibration; inverter-driven compressors can modulate capacity and reduce frequent start-stop cycles. | Compressor selection affects reliability, noise, energy use, and the unit’s ability to respond to changing spa loads. | Confirm compressor technology, rated operating range, overload protection, starting current, and availability of replacement parts. |
| Heat Exchanger Material | Titanium heat exchangers are generally preferred for saltwater, chlorinated, or chemically treated spa water because of their strong corrosion resistance. | The heat exchanger is directly exposed to spa water and is one of the most important components affecting service life. | Confirm the wetted material, tube construction, allowable water chemistry, and whether the exchanger is suitable for saltwater use. |
| Water Flow Requirement | Typical spa chillers may require approximately 2–8 m³/h, but the correct flow depends on cooling capacity and the heat-exchanger design. | Insufficient flow can cause poor heat transfer, nuisance alarms, or freezing risk; excessive flow can increase pump energy and pressure loss. | Compare the required flow range with the circulation pump curve, pipe diameter, filter condition, and total system pressure drop. |
| Ambient Operating Range | Many air-cooled units are designed for approximately 5–43°C ambient operation, although the exact range depends on the refrigeration circuit and controls. | Outdoor installations in hot climates may lose capacity or trip on high pressure if the unit is not designed for the local conditions. | Request cooling-capacity tables at the highest expected ambient temperature and confirm high-pressure safety settings. |
| Refrigerant | The refrigerant should comply with the destination market’s environmental regulations and service requirements. Lower-GWP options may be required in some regions. | Refrigerant restrictions, availability, and technician qualifications vary by country and can affect long-term serviceability. | Check the refrigerant type, charge quantity, safety classification, applicable local rules, and service documentation. |
| Control and Protection Functions | Essential functions include flow protection, high- and low-pressure protection, freeze protection, overload protection, temperature sensing, and automatic restart. | Protective controls reduce damage caused by blocked filters, low water flow, power interruptions, extreme temperatures, or abnormal refrigeration pressure. | Request the control logic, alarm codes, sensor specifications, restart behavior, and a commissioning or test procedure. |
| Electrical Compatibility | Common configurations include 220–240 V, 50/60 Hz, single-phase or three-phase power. The required configuration must match the installation site. | Incorrect voltage, frequency, phase, or protection sizing can cause poor performance, nuisance tripping, or equipment damage. | Confirm rated voltage, frequency, phase, maximum current, recommended breaker size, cable requirements, and earthing provisions. |
| Noise and Vibration | For installations near homes, hotels, or treatment areas, a sound pressure level below approximately 60 dB(A) is generally more comfortable, subject to measurement distance and conditions. | Noise complaints can reduce customer satisfaction and may limit where the chiller can be installed. | Request sound measurements with the stated distance, ambient conditions, fan speed, and installation configuration. |
| Ingress and Outdoor Protection | Outdoor equipment should have an appropriately protected enclosure, corrosion-resistant cabinet treatment, weatherproof electrical components, and suitable drainage. | Humidity, rain, salt air, and chemical vapors can accelerate corrosion and cause electrical failures. | Check the enclosure protection rating, cabinet coating, fastener material, drain design, and suitability for coastal or humid locations. |
| Installation and Maintenance | The design should allow access to filters, electrical components, heat exchangers, fans, sensors, and service valves without dismantling major assemblies. | Simple maintenance reduces downtime and lowers labor costs over the equipment’s service life. | Review installation clearances, piping diagrams, maintenance intervals, cleaning instructions, spare-parts lists, and service manuals. |
| Quality Documentation | A reliable product package should include a specification sheet, wiring diagram, refrigeration data, installation manual, operating instructions, and test records. | Complete documentation helps distributors, installers, and service technicians commission the unit correctly in different markets. | Request documents before ordering and ensure all electrical, refrigerant, performance, and safety data are consistent across them. |
| International Compliance | The equipment should meet the applicable electrical safety, electromagnetic compatibility, pressure-equipment, and environmental requirements of the destination market. | Compliance reduces customs, installation, insurance, and regulatory risks for international buyers. | Verify applicable declarations, test reports, labels, manuals, and certification scope for the exact model and electrical version. |
| Warranty and Spare Parts | A practical supply program should clearly define warranty duration, response time, exclusions, consumables, and the availability of critical parts. | After-sales support is essential because compressors, controllers, sensors, fans, and pumps may require replacement during the equipment life cycle. | Obtain written warranty terms, recommended spare-parts stock, technical support channels, and estimated parts lead times. |
