1. While working on pressurized parts (pipelines, heat exchanger components) depressurize before servicing.
2. Sharp edges and corners (especially in the fins) can cut fingers and hand. It is advised to wear protective gloves.
3. The maximum operating pressure specified on name plate should not be exceeded.
4. Installation and maintenance to be performed only by qualified personnel who are familiar with this type of equipment
5. Some units are pressurized with dry air or inert gas. All units must be evacuated before charging the system with refrigerant.
6. Make sure all power sources are disconnected before any service work is done on units.
7. Suitable firefighting equipment must be provided on site when working with flames, e.g. grinding, welding, soldering etc.
8. Make sure that all field wiring conforms to the requirements of the equipment and all applicable national and local codes.
9. While working on fan motor or removal/installation, it is advised to disconnect the power supply. The system must be secured against unintentional reactivated.
10. NH3 is toxic gas, pungent-smelling gas hazardous to eyes, mucous membranes and other unprotective areas of skin. Its effect generates unrest, dizziness, vomiting and cramps. Stronger concentrations cause symptoms of suffocation and life-threatening lung disease.
11. While work on the thermostatic expansion valve (e.g. adjusting overheating, changing nozzle inserts) must be performed by trained and qualified personnel only. All of the work referred to above must be documented.
12. Danger of frostbite (freezing of unprotected parts of the body) when touching heat exchanger parts and piping at refrigerant temperatures below 0 °C when refrigerating and danger of burns when touching heat exchanger parts, electric heating equipment and piping at temperature above 60 °C during defrosting 
13. During troubleshooting after HFC refrigerant breakaway releases, please be aware of remaining HFC refrigerant under defervescence as splashes can lead to frostbite on skin and eyes.
14. If the unit is installed close to the possible heat sources with danger of occurrence of high temperatures: take effective measures to protect the unit from excessive heat

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