Air-cooled modular cold and hot water unit configuration and takeover notes

Air-cooled modular cold and hot water unit configuration and takeover notes

The air-cooled modular hot and cold water unit is a combination of independent air-cooled heat pump units. At present, the modular unit is a very good model in the commercial air conditioning market. Its advantage is that it can change the number of modular unit units according to the user's load situation or allow users to add more units during use, so that users can flexibly purchase and use units according to their own funds and usage.

　　 1. The scope of application of air-cooled module cold and hot water unit:

　　1. Refrigerant: The market is mainly sold by R22, R410a, and R407C units.

　　2, power supply: 380V/50Hz/3H

　　3. Cooling capacity range: 15RT-75RT (that is, 61KW-261KW). In general, 15RT modules are used as the basis for combination. When compared with any manufacturer, the cost performance of 15RT modules is also the best.

　　4. Applicable environmental conditions and temperature of cold and hot water in and out:

　　1) Refrigeration: Environmental conditions: 21°C~43°C, refrigerant water inlet and outlet temperature: 12/7°C; the higher the outdoor ambient temperature, the worse the cooling effect.

　　2) Heating: Ambient conditions: -15°C (theoretically) ~ 20°C, heating medium water inlet and outlet temperature: 40/45°C (in general); the lower the outdoor ambient temperature, the worse the heating efficiency.

　　 2. Selection of the type and number of air-cooled module hot and cold water units

　　 1. Choice of type

Generally speaking, when the nominal cooling capacity of a single unit is less than 116kw, the scroll compressor is the main choice; when the capacity of a single unit is between 116kw and 700kw, it is better to use a screw compressor; when the capacity of a single unit is between 700kw and 1054kw, it is better to choose Screw machine or centrifuge is suitable; when the single machine capacity is above 1785kw, centrifuge should be selected.

　　2, determine the number of units

　　The number of units should be determined according to the size of the project and changes in air conditioning load. From the perspective of flexible adjustment and conducive to energy saving, more units are better; from the perspective of equipment investment, floor space, and maintenance management, fewer units are better. Generally choose 2-8 units. For a dual-compressor modular machine, up to 8 z* can be connected in parallel, that is, 1 main machine and 7 sub-machines; for a 4-compressor modular machine, up to 4 z* can be connected in parallel, that is, 1 main machine and 3 sub-machines.

　　 Three, the basic configuration of the unit

　　1, scroll compressor

　　2, plate heat exchanger

　　3, fan motor

　　4, coil

　　5, electrical control components and other components.

　　 Four, water pipeline installation

　　1, same program

　　2, different program

　　 Five, takeover matters needing attention

　　 1. The inlet and outlet water mains, valves, filters and other components of the unit water system should adopt the same specifications. Vibration damping throats are used to connect the pipes between the units.

　　2. The air release valve must be installed at the high point of the water system. The system direction should not have too many and too sharp elbows.

3. When the circulating water runs for the first time, please close the bypass valve on the inlet and outlet sides of the unit, install a temporary filter on the main pipeline of the unit, turn on the water pump, and pre-clean the waterway until all impurities in the waterway system are removed, confirm the water The unit can be put into use only when there are no impurities in the system.

　　4. When installing the inlet and outlet water temperature sensor, a blind pipe needs to be inserted into the center of the pipeline to reduce the thermal resistance between the sensor and the refrigerant water.

　　 5. The combined modular units must be of the same model. If there are more modules in parallel, the modules can be arranged in two rows. Please note: There should be space for operation and maintenance on the side of the electric control box, and the distance between two rows of modules should be at least 0.5m.

　　 6. The external water pipe of the unit needs to be installed and supported.

　　7. Installation plan: 1 to 2 units can be installed in the same way or in different ways, and 3 or more units are recommended to be installed in the same way.

　　 Six, installation precautions

　　 1. A water filter must be installed, otherwise it will cause failures such as frost damage to the unit board.

　　 2. Before the unit runs, a trial run is required to remove impurities in the pipeline.

　　3. When it snows in winter, sweep away the snow on the coil to prevent damage to the compressor.

　　 4. Unless there are special requirements, the unit generally does not have a built-in water pump.

　　 5. The water flow switch should be installed in the water outlet pipe close to the unit.

　　 6. The filter of the unit needs to be cleaned regularly.

　　7. When installing multiple machines, ensure sufficient suction space to prevent short circuit circulation.

　　 8. There is a standard damping plastic cushion on the base of the unit pallet to reduce the transmission of vibration and vibration.

　　 9. When installing the cooling and heating unit on the ground, the unit should be at least 20cm above the ground for drainage.