CASE STUDY

AIR-CONDITIONERS

An Investment in Longer Lasting Quality

BT Commercial Ltd. is a dynamic and diversified company, which has been in operation since 1992. Our company, which is growing from strength to strength and proudly represents some of the world leading brands in air-conditioning, photovoltaic, solar water heater and industrial refrigeration systems.

We have now moved our core business to High Technology and Renewable Energy products and installations. We have a well-structured set-up for all our operations which includes modern offices, showroom and warehousing facilities to complement our well trained office and technical staff.

BT Commercial Ltd. specialises in the design, installation and commissioning of mechanical services for all types of commercial, industrial, public and private projects as well as communal housing projects. Our specialised field also extends in providing air-conditioning, heating and cold-water solutions too. It is our general policy that while executing all our operations we ensure that all necessary health and safety measures are applied.

BT Commercial Ltd. operates an equal opportunity policy and manages all its business operations with due regard to environmental and sustainability issues. We strongly believe in longstanding client relationships and strive to understand their needs.

ABOUT US

LUNA HOLIDAY COMPLEXCASE STUDY

The Challenge

BT Commercial Ltd. have been entrusted for the Installation and commissioning of the air-condition system at the Luna Hotel in Mellieha. Great attention was taken for the installation of the equipment for this project as our task was mainly to reduce energy consumption and achieve cost management control. For this reason our team have set guidelines to be followed for this project to enhance system performance, energy saving and customer satisfaction.

Works Commenced

• Installation of new water cooled chillers.• Installation of new chilled water air conditioning units in guest rooms and in hotel foyer.• Installation of new chilled water pipework

Guidelines

•Computer control and monitoring system as to run the whole air-conditioning system in the best and most economical way and maintain the best temperature control.•Energy saving system. Long Distance System MonitoringGREE long distance monitoring software was installed on a computer. This system canmonitor and control air-conditioning systems keeping the machinery under control at all times. This reduced operation costs as the most appropriate unit operation modes can be easily set. It also reduced maintenance costs as errors can be easily detected via the auto recorded air-conditioner operation state data.

The Solution

The best solution for this project was the following:GREE Water Cooler Chiller

Description

With a wide cooling capacity range from 180 to 1280kW, GREE water-cooled screw chillers are being selected by more and more users for high efficiency and absolute dependability. GREE chillers are new widely applied in hotel, apartment, restaurants,

office buildings, shopping mall, theatre, gymnasium, hospital and so on, as well as supplying cool water for machine cooling purpose based on customized design all over the world.

Standard Specifications

High Efficiency Full Load OperationUtilizing new screw compressor technology, the chillers meet or exceed the performance requirements of ASHRAE 90.1. All system components are selected for optimum performance, including the condenser and evaporators sizes.

Capacity ControlStep or step less capacity control are optional available, enable the unit to be turned on with the least load to reduce start-up current, and match up capability output of units to actual load, which make the units operate steadily and reduce operation cost.

CompressorCompact suction gas cooled semi-hermetic twin screw compressor with high efficiency performance curve. Compressors are provided with high efficiency suction strainer, oil trainer crank case heater and built-in safety pressure relief valve. Compressors are also provided with intelligent electronics including motor temperature monitoring, phase reversal protection, manual reset lock-out and discharge temperature protection by PTC’s sensors. Optimized oil management ensure minimum refrigerant dilution in oil.

CoolerFlooded type, shell-and-tube type with refrigerant evaporated inside the shell and water flowing in the tubes. With special high efficiency pool boiling heat-exchange tubes, which are expanded into a steel plate, the flooded type structure enable both the theories of pool boiling and nucleation boiling is well applied. Thus, the uniform refrigerant distribution, optimized temperature field of heat transfer, heightened evaporating temperature are achieved, and cooling capacity and EER of unit are improved greatly. All evaporator are designed, constructed and stamped according to the requirements of the ASME Boiler and Pressure Vessel Code.

CondenserThe condenser is shell-and-tube type, carbon steel fin and seamless high efficiency copper tubes with refrigerant condensing inside the shell and water flowing through the tubes. Each condenser is designed, constructed, inspected and stamped accordingly to the requirements of the ASME Boiler and Pressure Vessel Code.

Reliable Oil ReturnIn order to ensure the oil in refrigerant system returns to the compressor, the secondary oil separator with both centrifugal and absorption setups is used for improving efficiency of oil from refrigerant, and a kind of injection equipment of refrigerant designed which can be a great help of oil returning into compressor from refrigeration circuit, at the same time, the low oil location protection is applied to avoid the damage to compressor from low oil to ensure reliability of the chillers.

Strict Out-going TestEach unit will be tested strictly not only on normal operation condition but also minimum/maximum operation condition when leave factory by advanced on-line test system.

Control PanelThe control panel provides a friendly interface for the operator with the color touch LCD (liquid crystal display) which can display chillers operating status, diagnostic message and date curve.

Superior ControlsGREE had provided the latest technology in controlling the chillers. The control logic is designed to provide maximum efficiency, to help provide continuous operation in unusual operation conditions through proactive controls, and to provide the history record of operating to aid in trouble shooting. Protocol for integrating with your building automation system (BAS) are optional available.

Standard Accessories

New Throttling SetupThe new throttle setup can calculate optimal value of EER through control logic, and adjust it automatically from actual value to optimal value, because refrigerant flux and the high of liquid in flooded evaporator can be control accurately by electronic expansion valve, the efficiency of unit will be maximized in either full load operation or part load operation.

Water Flow SwitchWater flow switch is available for field installation in the chilled water piping to protect against evaporation freeze-up under low, or no flow conditions. Interface are provided in the unit control centre for field connection of the water flow detection switch. The flow detection device need to be prepared on field.

Pump Control OutputProvides a digital output to control the secondary chilled water pump. Standard unit has one pump control output.

Unit On-Off SwitchON-OFF switch is provided for manually switching the unit control circuit.

Indicator LightsLED lights to indicate power on of unit, running state and fault.

Filter DrierRefrigerant circuits are kept free of moisture, sludge, acid and oil contamination by filter drier.

Under Voltage and Phase ProtectionProtects against low voltage as well as phase fault reversal.

Sight GlassA color indicator shows moisture content and provides a mean for checking the system refrigerant.

Liquid Line Solenoid ValveIt will be closed when the compressor is off to prevent any liquid refrigerant from accumulating in the evaporator.

Standard Control & Safety Devices

Safety ValveProtecting the unit against high discharge pressure.

Compressor Built-in Protection DeviceMotor winding temperature, discharge gas temperature and phase reversal for direction of rotation.

Crankcase HeatersProtects the unit against/from refrigerant migration, oil dilution and potential compressor failure.

GREE Chilled Water Air-Conditioning Units.

GREE FP series fan coil air conditioners are designed specially to meet the varied requirements of zone cooling or heating using chilled water or hot water. Fan coils can be applied to two or four pipe systems to satisfy the requirements of a wide variety of air conditioning or heating application. GREE FCU (Fan Coil Unit) is available in concealed and exposed versions for ceiling and floor mounted installation. They offer effective zone control and are especially suitable for use in apartments, hotels, shopping centres, office buildings and hospitals. GREE FCU is available in four configurations: WA- Concealed Ceiling; WM- Floor Ceiling Type; XD- Cassette type; B-Wall mounted.

System Installed

Water Cooled Chiller -

LSBLG240H/Nb-M (2 In No.)Nominal Cooling Capacity - 238 kW

Chilled Water Indoor Units FP -68BA2/A-K (130 In No.)Wall Mounted TypeNominal Cooling Capacity – 3.6kWNominal Heating Capacity – 5.4kW

FP -85BA2/A-K (40 In No.)Wall Mounted TypeNominal Cooling Capacity – 4.2kWNominal Heating Capacity – 6.3kW

FP -136WA-K (7 In No.)Duct TypeNominal Cooling Capacity – 7.35kWNominal Heating Capacity – 11.0kW

Luna Holiday Complex opened its doors in 1982, starting off with 30 apartments. Throughout the years it has expanded its business and presently enjoys 158 apartments. Luna Holiday Complex is presently one of the leading three-star apart-hotels in Malta and has continued to enhance its expertise in the hospitality industry.

Located in the idyllic town of Mellieha in the northern part of the island, Luna Holiday Complex is within walking distance from Mellieha Bay, Malta’s largest and most popular sandy beach. Enjoying a prime location close to the beach, discover an astonishing range of activities and water sports at the beautiful beaches nearby!

ABOUTLUNA HOLIDAY COMPLEX

A BT Buildings, No. 300, St. Thomas Street, Tarxien TXN1602, Malta.

T (00356) 2180 6614 / 2182 1596 / 2166 7711 / 2700 8036

M (00356) 9943 4566 F (00356) 2180 5546

E info@btmalta.com W www.btmalta.com

Energy Efficiency. The Natural Choice.

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