Heat Pump Evaporator Tubes | Air Source Heat Pump Evaporator Tubes

Heat pump evaporator tubes are specially designed enhanced tubes for air-to-water heat pump evaporators. Unlike standard AC evaporators, air source heat pump evaporators operate under low ambient temperature conditions, with evaporation temperatures as low as -15°C to -25°C. This demands exceptional low-temperature heat transfer performance and freeze resistance from the tubing.

Kenergy's heat pump evaporator tubes feature optimized internal groove parameters that maintain a high heat transfer coefficient even at low evaporation temperatures and low refrigerant mass flux. The wall thickness is carefully designed with an additional safety margin to resist freeze-induced cracking. These tubes are compatible with a wide range of heat pump refrigerants including R134a, R410A, R32, and R290.

Core Advantages

Optimized for Low-Temperature Operation

Special groove profile design maintains efficient heat transfer across the evaporation temperature range of -10°C to -25°C, ensuring reliable heating capacity in cold climates.

Anti-Freeze Design

Redundant wall thickness combined with high-toughness copper material reduces the risk of tube rupture caused by ice formation during defrost cycles or extreme operating conditions.

Compatible with Eco-Friendly Refrigerants

Groove profiles optimized for mildly flammable (R32) and flammable (R290) refrigerants, balancing heat transfer efficiency with safety considerations for reduced charge systems.

Defrost Cycle Stability

Groove geometry promotes condensate drainage during defrost cycles, minimizing frost residue and ensuring consistent heating performance in subsequent operating cycles.

Technical Parameters

Standard specifications with thicker wall design for enhanced freeze resistance. Custom configurations available upon request.

Outer Diameter (mm)	Wall Thickness (mm)	Fin Height (mm)	Tooth Count / Starts	Helix Angle (°)	Compatible Refrigerants	Material
7.00	0.40–0.55	0.12–0.20	40–60 / 4–6	15–25	R134a / R410A / R32 / R290	TP2
7.94	0.40–0.60	0.14–0.22	50–70 / 4–6	15–25	R134a / R410A / R32 / R290	TP2
9.52	0.45–0.65	0.16–0.25	60–80 / 6–8	18–25	R134a / R410A / R32 / R290	TP2
12.70	0.50–0.65	0.18–0.28	60–80 / 6–8	18–25	R134a / R410A / R32 / R290	TP2

Typical Applications

Residential Air-to-Water Heat Pump Evaporators

Domestic heat pump water heaters and space heating systems requiring reliable operation in cold climate conditions.

Commercial Heat Pump Water Heaters

Large-capacity heat pump water heaters for hotels, schools, hospitals, and commercial hot water applications.

Air Source Heat Pump Heating Systems

Evaporators for air-to-water heat pump heating systems in residential and light commercial buildings.

Heat Pump Dryer Evaporators

Evaporators for heat pump clothes dryers and industrial heat pump drying systems.

Frequently Asked Questions

Q: Can heat pump evaporator tubes be substituted with standard AC inner grooved tubes?

We do not recommend direct substitution. Heat pump evaporator tubes are specifically designed for low evaporation temperature conditions (-10°C to -25°C) with optimized groove geometry and thicker walls for freeze resistance. Standard AC inner grooved tubes are optimized for higher evaporation temperatures (typically 5°C to 10°C) and may suffer from reduced efficiency and increased freeze risk when used in heat pump applications, especially in cold climates.

Q: What special requirements do R32 heat pump systems have for evaporator tubes?

R32 operates at higher pressures than R410A, and as a mildly flammable (A2L) refrigerant, safety considerations are paramount. For R32 heat pump systems, we recommend our specifically optimized groove profiles that balance heat transfer performance with reduced refrigerant charge. The tubes are manufactured with enhanced wall thickness consistency to withstand the higher operating pressures. Additionally, the groove geometry is fine-tuned for R32's thermophysical properties to maximize efficiency at low ambient temperatures.

Q: How do you prevent tube freeze damage in low-temperature environments?

Our anti-freeze strategy combines three approaches: (1) Increased wall thickness with a safety margin above standard AC tubes to withstand ice expansion pressure; (2) High-toughness TP2 copper material with excellent low-temperature ductility to accommodate minor deformation without cracking; (3) Groove geometry that promotes complete drainage during defrost cycles to minimize water retention. For extreme cold climate applications, we also offer enhanced wall thickness options upon request.

Q: Do you supply complete fin-type heat pump evaporator assemblies?

Currently, we specialize in manufacturing the copper tube components for heat pump evaporators rather than complete fin-type evaporator assemblies. However, we can supply matched tube-and-fin combinations in partnership with our authorized fin-stamping partners. If you require complete evaporator coil assemblies, please contact our sales team with your specifications, and we will connect you with an appropriate OEM partner who can fabricate the full assembly using our tubes.

Heat Pump Evaporator Tubes — Air-to-Water Heat Pump Evaporator Tubes