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28KW-40KW -25℃ EVI Air Source Heat Pump for Cold Weather Hot Water & Underfloor Heating

1. High Cop: 3.34/2.85/4.31

2. Power Supply: 380V~415V/50Hz/3ph

3. Running Temp: -25℃-45℃ (CGK/D-36(LHC)、CGK/D-36(L) )

Running Temp: -10℃~45℃ ( CGK/D-36(LH) )

4. Max Outlet Water Temperature: 55-80℃

5. Cooling: 10℃(Min Water Temp)

6. Heating Capacity: 28KW /31.5KW /40KW

7. Cooling Capacity: 26.8KW
  • CGK/D-36(LHC); CGK/D-36(LH); CGK/D-36(L)


Heat Pump Features

EVI Air Source Heat Pump for Cold Weather


SPRSUN EVI air source heat pumps are designed for domestic/commercial/industrial hot water heating and cooling in cold areas where lowest air temperature is above -25℃.



● Efficient and Energy-saving 

Air source heat pumps absorb hot energy from the air freely, and the electricity is only used to drive the compressor to pump up the heat from the air. So, it consumes just a quarter of traditional electric heaters, saving a lot of electric costs for users.  


 Green and Environmental Protection

By using air hot energy and electric energy, there is no harmful gas being discharged during the operation of heat pumps. Refrigerant guarantees fluoride-free emission. 


● Usable All-weather

All weather operation: stable operation without being influenced by any windy, rainy or snowy weather. 


● Endurable 

The Enhanced Vapor Injection (EVI) technology from Copeland compressor with crankcase heater for special cold area, Danfoss electronic expansion valve, Eaton AC contactor and thermal relay and other brand components of the heat pump guarantee high quality and a long lifespan. All of our screws and clips (both external and internal) are stainless steel. The cabinets we are using are made of GALVANIZED STEEL, making them more rust resistant, durable and affordable. 


● Multiple Protections

For example, if water flow is not enough in the system, the system will show high pressure protection and stop the heat pump automatically to protect the compressor from being damaged. Also, there is high current protection: if the power supply is not stable, the heat pump will show the high current error to stop the heat pump and avoid compressor damage.


● Linkage Function

External signal on/off function


● Guaranteed Safety

Complete isolation of water and electricity avoids electric shock, explosion and poisoning; LCD screen digital controller for automatic operation


● Convenient

The EVI heat pump is easy to install in many places, such as garage, balcony, kitchen, etc.



Heat Pump Specifications


  • Rated working conditions:
    Dry-bulb temp: 20℃; wet-bulb temp: 15℃; cool water temp: 15℃; 
    - Heating: air temp (DB/WB): 7℃/6℃;  Hot water temp: 45-75 ℃.
    - Cooling: air temp(DB/WB): 35℃/24℃, water temp (inlet/outlet): 12℃/7℃.
Heat & Cooling
Heat & Cooling
Hot water & floor heating
Hot water & floor heating
Hot water & floor heating
No Cooling
Power supply V 380V~415V/50Hz/3ph
Refrigerant R407C R134A
Heating capacity KW 31.5 41 20 26 40 28
Input power of heating KW 9.43 12.28 4.6 6 9.3 9.82
3.34 3.34 4.32 4.31 4.31 2.85
Cooling capacity KW 26.8 34.9 / / / /
Input power of cooling KW 9.74 12.67 / / / /
2.75 2.75 / / / /
Rated current A 17.9 23.3 8.8 11.5 17.6 18.7
Max current A 25.1 32.6 11.9 15.5 23.8 25.2
Fan motor power W 250 330 90 100 250 250
Fan motor quantity Piece 2 2 2 2 2 2
Water flow L/h 6019 7834 3822 4968 7643 8025
Water pressure drop Kpa ≤55 ≤60 ≤40 ≤45 ≤55 ≤60
Max Input Power KW / / 6.3 8.1 12.5 /
Hot Water Production L/h / / 430 559 860 /
Water Rate L/h / / / / / 401
Net weight kg 320 380 164 190 320 320
Gross weight kg 333 400 174 200 333 333
Noise db 65 68 56 58 65 60
Classification of waterproof IPX4
Electric shock proof grade I
Pipe size (internal thread) mm 32 40 25 25 32 32
Dimension mm 1450*740*1150 1500*800*1515 1090*480*1260 1256*565*1368 1450*740*1150 1450*740*1150
Packing dimension mm 1540*820*1320 1580*880*1665 1160*500*1410 1310*620*1520 1540*820*1320 1540*820*1320
Compressor model/quantity ZW61KSE*2 ZW79KSE*2 ZW61KSE*1 ZW79KSE*1 ZW61KSE*2 ZW61KSE*2


Heat Pump Application

SPRSUN EVI air source heat pumps can be applied for hot water and floor heating.

Wide Range of Applications: these EVI low temperature heat pumps could meet the hot water and house heating requirements of different places, such as villas, houses, schools, factories, hotels, hospitals, spa centers, sauna centers, greenhouses, flower gardens, farms, etc.


Application of EVI Air Source Heat Pump



Why can SPRSUN EVI heat pumps work at -25℃? 

Because of the Enhanced Vapor Injection (EVI) technology from Copeland compressor with crankcase heater for special cold areas, SPRSUN designed EVI gas piping system and controlling system make EVI air source heat pumps work stably in the low temperature condition. 


SPRSUN Copeland Compressor EVI Heat Pump


Heat Pump Components



Why can SPRSUN EVI heat pumps work at -25℃? 

Because of the Enhanced Vapor Injection (EVI) technology from Copeland compressor with crankcase heater for special cold areas, SPRSUN designed EVI gas piping system and controlling system make EVI air source heat pumps work stably in the low temperature condition. 


EVI Material.jpg



Installing Heat Pumps


It is easy to install SPRSUN EVI heat pumps, shown as the following Installation Diagram: 

EVI High Temp Heat Pump Installation Diagram



COP of heat pumps


The Heating COP of SPRSUN EVI Air Source Heat Pumps at Different Working Conditions:

Model Air temp ℃ Hot water temp ℃
W35  W45 W55
CGK/D-36(L) -25 2.21 1.85 1.5

-20 2.49 2.08 1.69

-12 2.89 2.41 1.97

-7 3.25 2.62 2.21

2 3.65 2.95 2.48

7 4.15 3.35 2.82

12 4.52 3.72 3.13

20 5.07 4.28 3.6

Model Air Temp ℃ Water Temp ℃
15-40 15-50 15-60 15-70 15-75

-7 2.44 2.32 2.21 2.12 2.06

2 3.05 2.9 2.76 2.65 2.57

7 3.09 2.93 2.79 2.68 2.6

10 3.15 2.99 2.84 2.73 2.65

15 3.25 3.08 2.93 2.82 2.74

20 3.38 3.21 3.05 2.94 2.85

25 3.55 3.37 3.21 3.08 2.99

30 3.73 3.53 3.37 3.24 3.14

workmanship of heat pumps


We care every detail on what you need!


Super Low Noise: Fitted cut clothes for compressor and strong pads to avoid vibration

Anti-corrosion: Aluminum edging                         

Exellent Welding Guarantee No Leakage: Four-way valve welding protection  


workmanship of EVI air source low temp heat pumps


Energy Saving: 30mm thickness for insulation to prevent energy lost

User-friendly Design: Ram design using machine wire

Reliability of the Connection: Adopt automatic stamping machine from Taiwan


energy saving EVI air source low temp heat pumps



economic analysis of heat pumps


Energy Saving Up to 75%: Compared with solar water heaters, gas water heaters and electric water weaters, the energy cost saved by SPRSUN air source heat pump water heaters is shocking.




Solar Water 


         Gas Water Heater

Electric Water


Heat source electicity solar+electricity natural gas liquefield gas electricity
Heat Value 860kcal/kw/h 860kcal/kw/h 9000kcal/m⊃3; 1080kcal/kg 860kcal/kw/h
Efficiency 450%

1/3 time use of

 electric heater

90% 85% 90%
Energy consumed per day 2.07kw/h 3.45kw/h 0.99m⊃3; 0.87kg 10.34kw/h
Cost $0.11/kw.h $0.11/kw.h $0.42/m⊃3; $1.1/kg $0.11/kw.h
Cost per day $0.23 $0.38 $0.42 $0.96 $1.14
Annual cost $84 $139 $153 $350 $416


Heat Pump Models


Related models are as below:

Related Products of EVI Heat Pumps



Heat Pump Technical Support


Our experienced engineering team provides good support for any questions concerning the products and installation before, during and after products are sold. 


Before Selling

  • Set up customers file and arrange professional sales engineers to introduce company products and services to customers in details.

  • If customers are interested in our products, we will send professional technicians to survey the installation environment.

  • Provide solutions according to different customers' requirements.


During Selling

  • Machine installed and tested by QA engineers.

  • Ensure all the products we provide are qualified and new. The working life of the main engine is 15 years.

  • Construct and install the heat pump according to national relevant policies strictly and ensure high quality delivery on time.

  • Test and debug the equipments strictly to ensure the safety and stability.

  • During the delivery, provide comprehensive and professional technical training on instructions and maintenance to customers.


After Selling

  • We promise to offer free consulting call in 7×24 hours mode to solve the problems found in practice. The number is 86-20-82181867.

  • Sprsun offers 18-month long warranty. Within 18 months since the delivery date, if the product has any failure under normal usage, Sprsun will provide free assembly parts.

  • After the expiration of the warranty period, we will continue to provide lifelong maintenance services, with just a small amount of charges.


Contact Us

Guangzhou SPRSUN New Energy Technology Development Co., Ltd.

A Professional Heat Pump Manufacturer Since 1999
No.15 Tangxi Road, Yinsha lndustrial Park, Xintang, Zengcheng , Guangzhou, Guangdong, China, 511338

Contact SPRSUN. 7/24 Support. We Will Reply You ASAP!

Tel: 0086-20-82181867
Phone: 0086-18933985692