The outdoor unit has been charged with refrigerant.
When connect the pipe to the unit or dismantling the pipe from the unit, please follow the figure shown, use spanner and torque spanner together.
When connect cone nut, the inner side and outside of cone nut should paste with refrigerant oil. Use hand to twist 
Referring to Table I to confirm the fasten torque. (too tight may damage nut leading to leakage)
Check if the connection pipe leaks, then do heat insulation treatment, as below figure shown. 
Only use seal cushion to bind the joint part of air pipe and heat insulation parts.
Spanner
HDU-42HF03/H specifications
The Haier HDU-42HF03/H is a remarkable addition to the world of cooling and heating solutions, designed to meet diverse climate control needs in residential and commercial settings. This sleek and efficient ducted air conditioning unit combines advanced technology with reliability, ensuring optimal comfort for users throughout the year.One of the standout features of the HDU-42HF03/H is its impressive energy efficiency. With a high Energy Efficiency Ratio (EER) and Coefficient of Performance (COP), it minimizes energy consumption while maximizing cooling and heating output. This sustainability-centric design not only reduces electricity bills but also supports environmentally friendly practices.
The unit employs inverter technology, which allows for variable speed control of the compressor. This means that the air conditioner can adjust its cooling or heating power based on the room's temperature, maintaining a consistent environment without the constant on-off cycling of traditional systems. This translates to quieter operation and longer equipment lifespan, as it reduces wear and tear on the components.
Equipped with advanced air filtration technology, the HDU-42HF03/H helps improve indoor air quality by trapping dust, pollen, and other allergens. This is particularly beneficial for individuals with respiratory conditions or sensitivities. The unit is designed for easy maintenance, with accessible filters that can be cleaned or replaced as needed, ensuring optimal performance over time.
The Haier HDU-42HF03/H is also notable for its climate adaptability. It can efficiently operate in various ambient conditions, making it suitable for different geographical locations. Its robust build quality ensures that it can withstand the rigors of daily use.
In terms of features, the HDU-42HF03/H offers a user-friendly control interface, enabling easy temperature adjustments and mode selection. Smart home compatibility allows users to integrate the system into existing smart devices, providing enhanced control and convenience.
Overall, the Haier HDU-42HF03/H stands out as a reliable and efficient choice for those seeking a versatile air conditioning solution. With its blend of energy efficiency, advanced technology, and user-centric design, it is well-equipped to provide comfortable living and working environments year-round. Whether for cooling hot summers or efficiently heating during chilly winters, this unit is a commendable option for modern climate control needs.