Mechanical cooling

         Free cooling

Indoor side

Temperature range and accuracy

18°C~35°C±1°C

5~45°C

Outdoor side

Standard unit

-10°C~50°C

-30°C~50°C

Optional unit

-30°C~50°C

-30°C~50°C

Dual cooling source

Each unit in the range is equipped with dual cooling system: compressor mechanical cooling system and fresh air free cooling system, of which the fresh air is the primary source of cooling.

Room positive pressure control

The unit has a damper which is set at a minimum opening position to introduce 3-5% external air into the conditioned space, when it is closed to assure a positive air pressure inside the conditioned area.

Self-contained

All the components including fans, compressor, evaporator, condenser, and controller are incorporated in a package. After the rain proof louver, air plenum between the unit and wall, air duct and power supply is installed; the unit can be started up to run normally.

Fully automatic control with manual control availability

The unit is equipped with a full automatic control system, All the control and protection and alarm is automatic. And furthermore, manual control for each component is available any time.

Automatic random restart

When power supply is recovered after a interruption, the unit will restart with a random time delay to avoid many units starting at the same time, to avoid interfere.

Working mode automatic change over

The unit automatically selects the working mode: mechanic cooling or free cooling according to the air temperature of indoor side and outdoor side. In the event of either electrical or mechanical failure affecting the refrigeration system, the unit will be capable of automatic reversion to the fresh air cooling mode.

Flange connection

The unit connection of air inlet and outlet is flange type and is capable of being connected to the distribution ductwork without the need for specialist fittings.

Easy maintenance

All the components inside the unit are installed with necessary clearance for maintenance and can be assemble or disassemble easily. The weight of each panel is less than 10 kg for easy handling.

Strong structure

The unit has a good structure with components securely mounted to in order to deal rough roads.

Smaller volume

Thanks to the good structure design and system design, the unit got fewer components, compact structure and got a smallest size, comparing with competitive products.

Obvious labels

There are necessary labels for safety warnings, operation and maintenance instructions. They are placed on the unit panels or at the relevant places inside the unit.

Dual circuit power supply

The unit is designed to be powered by 2 inputs. One is the essential power for supply fan, control circuit and air damper and the other one is non-essential power for compressor, condenser fan and electric heater.

EC motor for supply fan

The supply fan is single inlet back curved vane centrifugal fan equipped with EC motor, which has properties of low starting current (soft start), high efficiency, adjustable speed control etc.

High power factor

The power factor of all the units at all working conditions is higher than 0.9.

Standard air filter

The air filter for this series units are all standard one as the following table. The thickness of filter is 2 inches. And the installation frame for the filter can contain either 2 inches or 4 inches air filter. The material of both frame and filtering material are made of combustion resistance material.

Anti-corrosion

All the unit frameworks,panels, heat exchangers is provided with corrosion protection treatment. The treatment is to provide protection for a minimum of 15 years

Heat insulation and sound absorption

Panels are lined with heat insulation, sound absorbent and fire retardant materials, which are tear resistant, smooth, wipe clean surface.

Big air flow

In order to be suitable for the features of high sensible heat of machine room, the units are designed according to big air flow and small enthalpy difference. The supply air temperature is over 15°C when it is working at mechanic cooling conditions. The sensible heat ratio is higher 0.9 for all the units.

High return air temperature

The unit can work continuously at maximum 45°C dry bulb with 29.5°C wet bulb return air conditions.

High performance air filter

The air filter has a big dust content capacity with low pressure drop. The nominal air flow rate will not be reduced by more than 10% with 250Pa pressure drop.

Low leakage and high rotation torque air damper

When the air damper is at its closed position, the air leakage through the damper will be not greater than 5% in volume which the air passes through the unit when a reverse pressure of 125 Pa is applied to the damper. The air damper has a big rotation torque to make sure that it can fully open from close position within 90 seconds.

Power consumption logger (Optional)

A power meter can be an option for power consumption measurement and logging, which allows the user to know the energy consumption rate and to optimize the unit running.

Comfort mode function

The control software support comfort cooling mode function, which is specially designed allow a field staff to easily select a more comfortable cooling set point of 24°C instead of the default set point of 29°C. The comfort mode set point adjustment will time out to the default after a pre-defined period (default is 30min).

Multilevel access password

The unit has a 4 access levels password protection.

Power supply protection

The unit is supplied with a power protection relay with the protection of phase failure, over voltage, under voltage for both essential and non-essential electrical supplies.

Random delay startup

In order to avoid unit startup at the same time when power recovered after a power interruption, the control software is designed with a random startup time delay function. The delay time is between 5 and 120 seconds.

Serial alarm and ordinary alarm

The unit control system monitor and control the working status of all the components of the unit. If there is an abnormal phenomenon, an alarm will be generated.

Humidity control (Optional)

The unit is able to install a humidity sensor to monitor or control the room humidity under a preset value and protect outside humid air entering the room.

Automatic work hours/load balancing

If the unit is installed with 2 compressors, the compressor working time is balanced by rotating the lead-lag compressor for every 24 hours.

Step-less condensing head pressure control

The condenser fan rotation speed is step-less controlled or regulated by the condenser pressure. This allows the unit to run more stable and more efficient.

Automatic maintenance test

A maintenance test program is provided. A field tech just need to press one button to activate a self-test routine. The self-test routine will check for the satisfactory operation of the fresh air damper and the compressor refrigerant circuits.

Running data logging

The unit controller logs automatically the unit running parameters every 5 minutes (which is adjustable). The parameters include:

DX set point

FA set point

Main fan hours run

Main fan minimum speed hours run

Compressor(s) hours run

Return temperature

Supply temperature

Outside air temperature log.

The controller is able to save 1M bytes of data.

Data output

A facility for a connection (RS232 D plug, or RJ45) of a computer leads to enable automatic downloading of logs and parameters into either a CSV file or Excel file. These data include:

Controller type

AHU type

Refrigerant charge per circuit

Air filter size and quantity

Programmable control functions

The unit is controlled by programmable micro-processor controller, in which there are many parameters can be set or changed by service engineer for customizing according to the real working conditions.