Job References
  • Hong Kong

    CIC Zero Carbon Building
  • China

    Canon Zhongshan Business Machines Co. Ltd.
  • Macau

    Macau Venetian Phase V & VI
  • Malaysia

    Bangsar Shopping Centre
  • Singapore

    Singapore Marina Bay Sands


Free Control Variable Frequency Modular (Heat Pump) Chiller


SMVA modular variable frequency air cooled (heat pump) chiller is a central air conditioning system suitable for office building, hotel, restaurant, school, hospital etc. It is based on SAIVER® modular patent technology, combines with new technology like network communication & separate control, variable frequency control etc., which makes energy-saving, flexibility and reliability of modular chiller up to a higher technical level.

SMVA chiller is combined with network communication separate control system and the data communication between FCU and SMVA. The start of any FCU will give running instruction to SMVA. While the SMVA main controller will regulate cooling output automatically according to each FCU cooling demand. Therefore, SMVA is an intelligent central air conditioner under free control without computer room and special operator, it is more energy saving, flexible and reliable than VRF air conditioning system.

SMVA is constructed of modular combination, customers can select appropriate numbers of module to obtain desired total cooling capacity. In addition, one module per chiller contain variable frequency, compressor to regulate in range of 30-90Hz, min. cooling capacity output is only 3.5tons and max. cooling efficiency up to EER 18 (COP5.26) , which has greatly reduce power consumption while achieving the min. cooling demand.

Modular, Variable Frequency, VWF - Energy Saving

For VRF air conditioning system, compressor feeds refrigerant to indoor unit for direct evaporating (cooling) or condensing (heating), to cool or heat indoor air. If the refrigerant pipe length between indoor and outdoor unit is too long, the refrigerant pressure loss caused by piping, especially the pressure drop formed in suction line will force the compressor running with higher compressing ratio, thus greatly decrease cooling efficiency.  The longer length of the pipe, the bigger efficiency loss will be. What's more, to ensure compressor oil recovery at low load, it has to operate overload more often. Overlong piping may even cause ad normal system operation.

SMVA transfers cooling or heating capacity to room through feeding chilled/hot water, the chilled/hot water power change along with piping length is much less than the way of feeding refrigerant directly. When equivalent length of single way distance is over 50m, the cooling efficiency of SMVA is higher than VRF air conditioning system.

For chiller consisting of multiple SMVA modules, using variable frequency combined with constant frequency will meet the requirement for energy saving and economy. One module is variable frequency system, with working frequency in range of 30 -90Hz, min. cooling capacity output is only 3.5tons and max. cooling efficiency up to EER 18 (COP5.26) (Part Load Condition). While other modules running at nominal frequency, on or off according to cooling demand. This way satisfies the change of system load demand and will save 15% power than normal chillers.

A high reliable vertical pump is installed inside each module of SMVA chiller, it runs with modules synchronously according to system load demand. In this way, it will not only reduce compressor running at low load, but also reduce the power consumption of water pump to minimum.

Simple Installation, High Reliability

Since VRF air conditioning system uses copper refrigerant pipe to connect outdoor and indoor units, refrigerant leak and its imperceptibility due to pipe connection fault will greatly affect the system working efficiency, and induce expensive long term maintenance cost.

For SMVA system, normal water pipe is used to connect outdoor and indoor units, the installation of water system is much simple than that of refrigerant pipe system. Water leakage is easy to detect, repair cost is low and do not affect chiller system performance.

SMVA chiller consists of multiple modules, each module is independent refrigeration system and back up for each other. Fault of individual module won't cause the chiller shutoff, service and maintenance can be processed to the fault module without affecting the whole system operation.

Convenient & Flexible

SMVA Free-Control system uses network communication to connect outdoor chiller and indoor fan coil unit, anyone runs the fan coil unit through fan coil controller will start the outdoor chiller.

Similarly, when no fan coil unit is running, Free-Control system will automatically shut down the outdoor chiller.

When the outdoor chiller is in operation, Free-Control system will automatically regulate the unit running numbers and output load based on demanded cooling capacity to avoid over output.

Add-on Flexibility

The chiller consist of 16 modules the max. to form a system when necessary, and pipe size has a certain abundance, just add on new modules to increase unit capacity without any change to the system. Similarly, you can also purchase and install the chiller by stages to improve the capital usage.

Low Noise

SMVA uses low rotary speed axial fan which greatly lowers the chiller operation noise.  Optional variable speed fan will control the fan rotary speed according to ambient temperature and running pressure, this enables the fan operate quietly under low temperature and greatly reduce fan power consumption. Since the unit running at part load in most of time, the variable frequency drive compressor also working in a quiet status in most of running hours.

Environment Friendly SMVA

SMVA uses high efficiency environmental friendly refrigerant R410A recommended by EU, and compact brazed plate heat exchanger, which makes the refrigerant charge reduce 40% than normal chillers, and enables the manufacturer and user taking on their liability - reduce carbon emission and protect our earth.

Optional Features

Energy-saving heat recovery system

Install a stainless steel brazed plate heat exchanger within each module as heat recoverer, every bank unit is equipped with a hot water accumulator and circulating pump. Heat recovery system recover part of the heating capacity from compressor under cooling operation to obtain free and hygiene hot water.

Hydraulic balancing module

Hydraulic balancing module is integral functional module, consists of hermetic fixed pressure expansion tank, auto water supply valve and pressure differential bypass valve. Without open expansion tank, the system will free from external pollution and avoid the pump over-head at low load.

Remote monitoring system

The controller can connect to a PC to monitor the chiller operation via RS485 serial port to ensure safe and reliable operation.

SMVA Control System

SMVA control system consists of main controller MASC, room controller TC, and repeater hub CONNECTOR. The system is structured of network communication and uses RS485 serial port. Among the tree-type network, CONNECTOR can be treated as central node of a sub-area, each CONNECTOR has four ports, two of them are for connecting with max. 32 TC for each port, and total 64 TC for two ports.

The other two ports of CONNECTOR, one is for connecting with fresh air handling unit FAU. Once there is a TC start operating in the sub-area where the CONNECTOR located, it will start FAU at the same time. Similarly, when all TC in sub-area closed, it will also shut down FAU unit. Another port is used for connecting with PC, CONNECTORs together to form a larger network group.

When pressing ON of any TC in the system to start, it will give a call to outdoor unit through this network and awake the SMVA unit to start. If the whole TC in the network are OFF, MASC will shut down SMVA unit, the SMVA unit is in sleep mode and wait for next call.

MASC Main Controller

MASC main controller is based on SAIVER® advanced computer control technology, providing powerful control and protections for SMVA free control variable frequency modular chiller. It controls the below parameters:

- Chilled (hot) water leaving temperature

- Max. running load limit

- Load/unload delay time

- Auto on/off timing

MASC main controller monitors chiller fault conditions below, and shut down compressor or chiller when fault occurs, a fault alarm will be activated at the same time:

- High discharge pressure

- Low suction pressure

- Compressor overload

- Low evaporating temp.

- Low CH.W.L.T

- Loss of chilled water

The setting or modification of all control and protections should be passed with computer password to prevent important parameters being modified by unauthorized personnel. MASC main controller will accumulate automatically the running hours of each compressor and hence establishes working sequences to ensure each compressor has even running hours.

TC Fan Coil Temperature Controller

SAIVER® provides two types of special TC fan coil unit temperature controller, using to control indoor fan coil unit, water supply regulation valve, and communicate with outdoor SMVA unit to call for its operation. The basic functions and technical data of TC are as below:





Set and display indoor temperature

Cooling/heating/ventilation mode

Fan rotary speed manual/auto

Fan coil motorized valve control

Technical Data

Temp. range


Temp. control precision


Input power


Power consumption


Serial port


Output signal

On/off signal used for on-off motorized valve

4-20mA analog signal used for proportional motorized valve