1. How Does an Air Source Heat Pump Work?
Air source heat pumps absorb heat from outdoor air and transfer it indoors for space heating, cooling, and hot water production. Even at low ambient temperatures, modern inverter heat pumps can operate efficiently.
High efficiency: Up to 4–5 times more efficient than electric heating
All-in-one solution: Heating, cooling, and domestic hot water
Renewable energy: Utilizes free energy from the air
Low carbon emissions: Supports sustainable building goals

R290 and R32 are two common refrigerants used in modern heat pumps. R290 offers lower environmental impact and higher outlet water temperatures, making it increasingly popular in Europe.
| Key Feature | R290 | R32 |
|---|---|---|
| GWP | 3 | 675 |
| Max Water Temperature | Up to 75°C | Up to 60°C |
| Environmental Compliance | Excellent | Good |
| Long-Term Market Outlook | Preferred Choice | Transitional Solution |
Why Choose R290?
Ultra-low environmental impact
Higher water temperature output
Better aligned with future regulations
Ideal for sustainable heating projects

Heat pumps provide a more energy-efficient and environmentally friendly alternative to traditional gas boilers. They can significantly reduce energy consumption and operating costs.
Higher efficiency: COP up to 5.0
Lower operating costs: Reduced energy bills
Reduced emissions: No on-site combustion
Multi-functional: Heating, cooling, and hot water in one system
| Comparison Item | Heat Pump | Gas Boiler |
|---|---|---|
| Energy Efficiency | COP 3–5 | 85–95% |
| Energy Source | Electricity + Renewable Air Energy | Natural Gas |
| Operating Cost | Lower | Higher |
| Carbon Emissions | Low | High |
| Heating Function | ✓ | ✓ |
| Cooling Function | ✓ | ✗ |
| Domestic Hot Water | ✓ | ✓ |
| Environmental Impact | Excellent | Moderate |
| Long-Term Savings | High | Limited |
Modern EVI heat pumps are specifically designed to deliver reliable heating performance in harsh winter conditions and low ambient temperatures.
Low-temperature operation: Down to -25°C or below
Stable heating output: Reliable winter performance
EVI technology: Enhanced efficiency in cold regions
Ideal for northern climates: Suitable for Europe and North America

Underfloor heating systems operate at lower water temperatures, making them an ideal match for high-efficiency air source heat pumps.
Low-temperature heating: Perfect system compatibility
Higher energy savings: Improved seasonal efficiency
Uniform comfort: Even heat distribution
Quiet operation: Enhanced indoor comfort
Selecting the correct heat pump capacity is essential for achieving maximum efficiency and long-term performance.
Building size: Heating area affects capacity selection
Climate conditions: Colder regions require larger capacities
Insulation level: Better insulation reduces heating demand
Professional sizing: Ensures optimal performance and efficiency
| dc inverter heat pump | Unit | NL-FLM30-100II/R290 | NL-FLM30-130II/R290 | NL-FLM50-160II/R290 | NL-FLM50-190II/R290 | NL-FLM80-250II/R290 |
|---|---|---|---|---|---|---|
| Heating capacity (A7C/W35C) | W | 10000 | 12800 | 16000 | 19000 | 25200 |
| Input power (A7C/W35C) | W | 2410 | 2970 | 3750 | 4530 | 5385 |
| DHW capacity (A7C/W55C) | W | 9500 | 11300 | 15500 | 16800 | 23300 |
| Input power (A7C/W55C) | W | 3150 | 3600 | 5000 | 5500 | 7580 |
| Cooling capacity (A35C/W18C) | W | 10000 | 11000 | 14000 | 16500 | 25900 |
| Input power (A35C/W18C) | W | 2950 | 3600 | 4260 | 5400 | 7800 |
| Voltage | V/Hz | 220V-240V-Inverter-1N | 380V-415V-Inverter-3N | 380V-415V-Inverter-3N | 380V-415V-Inverter-3N | 380V-415V-Inverter-3N |
| Rated water temperature | ℃ | DHW:55℃ / Heating:45℃ / Cooling:12℃ | DHW:55℃ / Heating:45℃ / Cooling:12℃ | DHW:55℃ / Heating:45℃ / Cooling:12℃ | DHW:55℃ / Heating:45℃ / Cooling:12℃ | DHW:55℃ / Heating:45℃ / Cooling:12℃ |
| Max water temperature | ℃ | 75℃~80℃ | 75℃~80℃ | 75℃~80℃ | 75℃~80℃ | 75℃~80℃ |
| Rated water flow | m³/h | 1.7 | 2.1 | 2.7 | 3.1 | 4.3 |
| Refrigeration | / | R290 | R290 | R290 | R290 | R290 |
| Rated of waterproof | / | IPX4 | IPX4 | IPX4 | IPX4 | IPX4 |
| Control mode | / | Heating / Cooling / DHW / Heating+DHW / Cooling+DHW | Heating / Cooling / DHW / Heating+DHW / Cooling+DHW | Heating / Cooling / DHW / Heating+DHW / Cooling+DHW | Heating / Cooling / DHW / Heating+DHW / Cooling+DHW | Heating / Cooling / DHW / Heating+DHW / Cooling+DHW |
| Compressor - Form | / | Double-rotor type | Double-rotor type | Double-rotor type | Double-rotor type | Double-rotor type |
| Compressor - Quantity | / | 1 | 1 | 1 | 1 | 1 |
| Compressor - Brand | / | Panasonic Full Inverter +EVI Compressor | Panasonic Full Inverter +EVI Compressor | Panasonic Full Inverter +EVI Compressor | Panasonic Full Inverter +EVI Compressor | Panasonic Full Inverter +EVI Compressor |
| Net weight | Kg | 105 | 112 | 145 | 150 | 175 |
| Noise level | dB(A) | ≤51 | ≤51 | ≤53 | ≤53 | ≤58 |
| Fan - Form | / | Full DC fan motor (low noise) | Full DC fan motor (low noise) | Full DC fan motor (low noise) | Full DC fan motor (low noise) | Full DC fan motor (low noise) |
| Fan motor | PCS | 1 | 1 | 2 | 2 | 3 |
| Water heat exchanger | / | Sweden SWEP Plate heat exchanger (Main road)+Denmark Danfoss Plate heat exchanger(EVI road) | Sweden SWEP Plate heat exchanger (Main road)+Denmark Danfoss Plate heat exchanger(EVI road) | Sweden SWEP Plate heat exchanger (Main road)+Denmark Danfoss Plate heat exchanger(EVI road) | Sweden SWEP Plate heat exchanger (Main road)+Denmark Danfoss Plate heat exchanger(EVI road) | SANHUA+Danfoss Plate heat exchanger |
| Auxiliary Element built-in French | / | 3KW | 3KW | 3KW | 3KW | 3KW |
| Circulation pump built-in SHIMGE | / | Inverter Water Pump (water head 12 meters) | Inverter Water Pump (water head 12 meters) | Inverter Water Pump (water head 12 meters) | Inverter Water Pump (water head 12 meters) | Inverter Water Pump (water head 12 meters) |
| Expansion tank built-in | L | 5 | 5 | 5 | 5 | 5 |
| Ambient temperature | ℃ | (-25℃ -- 43℃) | (-25℃ -- 43℃) | (-25℃ -- 43℃) | (-25℃ -- 43℃) | (-25℃ -- 43℃) |
| Inlet pipe diameter | mm | DN25 | DN25 | DN25 | DN25 | DN40 |
| Outlet pipe diameter | mm | DN25 | DN25 | DN25 | DN25 | DN40 |
| Net size | mm | 1080×499×970 | 1080×499×970 | 1080×499×1365 | 1080×499×1365 | 1080×499×1653 |
| Packing size | mm | 1120×510×1100 | 1120×510×1100 | 1120×510×1490 | 1120×510×1490 | 1120×510×1785 |
| 20'GP container loading | pcs | 44 | 44 | 22 | 22 | 22 |
| 40'HQ container loading | pcs | 92 | 92 | 46 | 46 | 46 |
| E.P Energy Level(EU certified) | pcs | 35℃ A+++ | 35℃ A+++ | 35℃ A+++ | 35℃ A+++ | 35℃ A+++ |
Heat pumps provide hotels with an energy-efficient solution for space heating, cooling, and large-scale hot water production.
Continuous hot water supply: Meets high occupancy demand
Lower operating costs: Significant energy savings
Scalable capacity: Suitable for small and large hotels
Sustainable operation: Supports green building initiatives

Founded in 2003 – Over 23 years of heat pump expertise
China–Singapore Joint Venture – Global vision, local excellence
800+ Employees – 2 manufacturing bases and 1 marketing center
200,000+ m² Production Area – 12 automated production lines
10 Certified Laboratories – Advanced R&D and product testing
1,000,000+ Units Annual Capacity – Reliable large-scale production
National High-Tech Enterprise – Innovation-driven development

Location + Application + Required Water Temperature – Share your project requirements with us
(Example: Hamburg + Hotel + 85°C)
Full Specification Sheet – Detailed technical information for product evaluation
Certificate Package – CE, CB, RoHS, ErP, ISO and other available certifications
Customized Quotation – Tailored product and pricing proposal for your project
Free Technical Consultation – Professional support from our experienced engineering team
NULITE – Your Trusted Partner for Sustainable Heating Solutions