1, Key points for comprehensive installation of the unit
Professional installation: To ensure stable operation of the unit, it is recommended that users entrust a qualified installation team to install the entire refrigeration system.
Nitrogen inspection: The unit has been filled with dry nitrogen gas at 8-12 bar before leaving the factory. Before connecting the system, please check the nitrogen pressure to ensure that the interior of the system is dry and free of impurities.
Waterproof and moisture-proof: The unit should be placed away from water sources to avoid water or humid environments, in order to prevent the risk of electric leakage and shock.
Dedicated power supply and grounding: The unit should use an independent dedicated power supply to avoid sharing with other electrical equipment. The grounding bolt is located next to the unit control box. Please connect the grounding wire correctly, and the cross-sectional area of the grounding wire should match the power line to ensure safe operation.
Insulation and Environmental Safety: After the unit wiring is completed, a 500V megohmmeter should be used to measure the insulation resistance of the circuit to ground, which should not be less than 5 megohms. Flammable and explosive materials are strictly prohibited from being stored around the unit, and good ventilation should be maintained. The ambient temperature should be controlled below 38 ℃ to prevent high temperatures from causing malfunctions.
Installation location and spacing: The unit should be kept away from heat sources, avoid direct sunlight, and set up drainage measures. The distance between the air-cooled unit and the wall should not be less than 500 millimeters to ensure effective heat dissipation.
Installation foundation and vibration control: The installation foundation of the unit needs to be flat and stable, with a horizontal inclination not exceeding 0.3%. Use shock pads or dampers to reduce vibration during unit operation, and take reasonable sound insulation measures to reduce noise.
Condenser heat dissipation and control system: The air-cooled condenser should ensure sufficient ventilation space, considering the direction and speed of air flow. The installation and commissioning of the unit control system should ensure accurate monitoring and adjustment of the unit's operating status, including parameters such as temperature, pressure, and current, and consider backup and fault alarm functions.
2, Key details of refrigeration system pipeline installation
Pressure drop and oil carrying speed: Ensure that the pressure drop in the pipeline is within the allowable range, and the necessary oil carrying speed (usually 8m/s) should be ensured for the return pipe, especially the rising riser, to ensure smooth return of lubricating oil.
Design of vapor-liquid separation and return oil: For systems with large load changes and evaporation temperatures below -40 ℃, a vapor-liquid separator should be installed. All horizontal suction pipes should be inclined towards the compressor, with a slope of not less than 0.3%.
Pipeline layout and insulation: The refrigeration high-pressure pipeline should be short and direct to avoid oil accumulation in concave points. Suggest insulation treatment for the suction pipe to limit the superheat of the suction and ensure that condensation water does not flow to the electrical part.
Pipeline fixation and cleaning pressure test: The pipeline should be reliably fixed, especially at the crossing holes or bends. After installation, carry out cleaning and pressure testing to ensure the cleanliness and safe operation of the system.
3, Instructions for refrigeration system accessories
Expansion valve: Choose an internally balanced or externally balanced expansion valve based on the pressure drop in the evaporator. For R22 systems, when the pressure drop exceeds the corresponding evaporation temperature by 1 ℃, it is recommended to use an external balance type.
Oil separator: Install an oil separator on the compressor exhaust pipe to prevent oil droplets from entering the subsequent parts of the system. Especially in units where the distance between the compressor and evaporator pipeline exceeds 30 meters, there are multiple oil traps, devices with poor oil return effect or multiple evaporator/condenser systems are used, and the evaporation temperature is below -30 ℃, it is recommended to install.
Liquid sight glass: Liquid sight glass is used to observe the flow state and water content of refrigerant.
Electromagnetic valve: prevents refrigerant liquid from entering the evaporator during shutdown.
Crankcase heater: Maintain the temperature of the lubricating oil to prevent it from boiling when the compressor starts.
Vapor-liquid separator: to avoid the phenomenon of "liquid hammer" caused by incomplete evaporation of liquid, and to protect the compressor from damage. In addition, it can also store excess refrigerant liquid, prevent excessive liquid from diluting the refrigeration oil inside the compressor, and help improve the overall operating efficiency of the system.
Filters and sensors: Filters remove impurities and moisture from the refrigerant. The pressure controller and temperature sensor monitor and control the pressure and temperature of the system to ensure safe operation.
Emergency shutdown device: To ensure the safety of personnel and equipment, the refrigeration system is equipped with an emergency shutdown device to quickly cut off power or refrigerant supply in case of system failure or abnormality.
