Ultra-low Temperature Air Cooled Heat Pump

9 ÷ 150 kW
R410a
Working range: -25oC~48oC
Max. hot water: 60oC

Introduction

VAWL air source heat pump unit is a brand-new ultra-low temperature product developed by Airwave. It integrates advanced energy-saving technology,  low-temperature heating technology, high-temperature hot water technology, heat recovery technology and modulare technology. With excellent reliability and wide opreating range, common heat pump can do cooling at maximum 48oC ambient temperature; low temperature type can run at the lowest -25oC ambient temperature; high temperature hot water type can produce 60oC hot water at highest.

Specially, the heat pump is designed for low ambient temperature area, providing heating, cooling and hot water to creat a comfort living place for people.

Features

1. Water-free Design

No touch between fin-tube heat exchanger and its support makes sure that the bottom of fins are kept ventilated smoothly. When heating, the condensation water of fins is drained smoothly and quickly, preventing the water from freezing due to the lower part of fins touching with the water, improving the heating capacity and stability of heat pump.

When fin-tube heat exchanger as evaporator, In the flow direction of fin cross section, the flow direction of refrigerant and air is opposite. It is a full counterflow design, which can greatly improve the COP of heating, compared with conventional heat pump.

2. Double-effect Refrigerant Circuit Design

Due to double-effect refrigerant circuit design, the unit doesn't use economizer during cooling. Two check valves replace four check valves to ensure the shortest pipeline flow and minimum resistance when heating. It effectively improves unit's COP.

Main circuit and auxiliary circuit both use electronic expansion valves. The electronic expansion control on main circuit ensures compressors operate at a reasonable suction super heat; another one on auxiliary circuit ensures compressors' exhaust air superheat and unit's supercooling.

3. Multi-step Energy Adjustment

Single unit have multiple refrigerant circuits and its energy adjustment can be maximum 4 steps.  Maximum energy adjustment is 32 steps under maximum module combination of 8 units, which is close to the effect of stepless adjustment. Controller can judge the load demand of system and adjust energy output intelligently, keeping the unit running at the lowest energy consumption.

4. Module Design

Unit adopts module design. Its controller can control 32 compressors at maximum, monitoring each compressor's running status in real time, balancing the running time of each compressor intelligently to extend the service life of heat pumps.

Cooling capacity / maximum modules' number

70kW                        16 units

90kW                         8 units

150kW                       8 units

200kW                       4 units

260kW                       4 units

5. Intelligent control

Interlock control with terminals, like FCU, AHU etc.

Remote ON/OFF control

Chilled water pump interlock control

System auxiliary heater interlock control

6. Intelligent Defrosting 

High-precision temperature sensor senses the change of system pressure and temperature under frosting condition accurately and select the best defrosting timing, which avoids the incomplete defrosting and frequent defrosting.

7. Optional RS485/RS232 serial port with Modbus Protocol

Units can be connected with building management system (BMS) via RS485/RS232 serial port and achieve centralized control.

8. Integrated Protection

Main protection has:

Compressor overload protection

Fan overload protection

High/low pressure protection

Insufficient water flow protection

Exhaust air temperature overhigh protection

Power supply protection

Anti-freezing protection

Water outlet temperature overhigh protection

Overcurrent protection

Main Parts

1. Enhanced Vapour Injection High Efficiency Scroll compressor

The heat pump uses enhanced vapour injection high efficiency scroll compressor; its motor is effectively cooled by low-temperature return refrigerant and maintains high efficiency running.  high-temperature high-pressure refrigerant gas is directly discharged after being compressed, reducing pressure and heat loss, increasing COP.

2. Electronic expansion valve

Unit uses 480-step electronic expansion valve for precise throttling control to match the refrigeration system dynamically so that the unit is always operating at the optimum COP.

3. Finned-tube source-side heat exchanger

Hydrophilic alumimum foil fins make the air flow more smooth, reduce frosting and improve heat exchange capacity; internally threaded copper tube not only increases the heat exchange area, but also enhances the disturbance performance of refrigerant.

4. Low noise axial fan

Airfoil, large chord length, and space twist patented blade with serrated; and, high efficiency internal rotor two- motor (optional). Low noise, low heat generation, low power consumption and long operating life; level 1 energy efficiency.

5. User-side heat exchanger

User-side heat exchanger uses patented new shell-and-tube type, easy to disassemble, clean and maintain. Its orifice shunt makes refrigerant distribution more uniform, compared with the baffle shunt or the shuntless of traditional shell-and-tube heat exchanger. It is smaller size but higher efficiency.