Air conditioning installation: what to watch out for during installation?

Air conditioning installation is a complex process that requires expertise and consistency. Many customers are surprised at how many steps are required to make a system work efficiently and reliably. Unfortunately, not all air conditioning service providers follow best practices. While installation shortcuts can speed up the job, they often lead to lower efficiency, higher operating costs and reduced comfort. This can cost the owner thousands of euros over the years. So what’s the secret to air conditioning installation?

If you expect a reliable, economical and comfortable system, it is important to understand the entire installation process. In this article, we’ll walk you through each stage, from planning to commissioning. This will give you the insight you need to choose a quality contractor.

Please note that air conditioning installation is not a DIY project. Thus, it should always be performed by a certified professional, and after reading this article, it will be clear to you why.

Data collection: the key to accurate installation

During the initial visit, a technician, professional representative or surveyor will inspect your existing system and/or gather the necessary data to develop an accurate design. This information will then be used by the installation team.

Depending on the situation, special equipment may need to be prepared before installation. Thorough information gathering greatly increases the chances of a quick and trouble-free air conditioning installation.

Arrival of the installation team and preparation for installation

You should receive a text message or a phone call confirming this before the technician or professional representative arrives.

Upon arrival, the installation manager will brief you on the work plan. He will check the details of the order, including the type of equipment, accessories and special requirements agreed at the inspection.

It is important not to skip this step to avoid misunderstandings or unnecessary mistakes.

While the inspection of the substrate is underway, the rest of the team will begin preparations, protecting the floors, preparing tools, and initiating safety measures such as disconnecting the electricity on the existing air conditioning system.

Preparing the site for the new air conditioning unit

Before the actual installation, it is often necessary to modify the original location of the air conditioning unit. This usually involves replacing the handles and leveling the base on which the new unit will be mounted.

Modern air conditioners tend to be larger and heavier than older models, so it is important to ensure a solid and level base. Proper bracket selection, which is chosen based on the load capacity and width of the outdoor unit, is most often used to properly mount the air conditioner.

The composite pad, the cantilever, is lightweight, weather resistant and better absorbs vibration, contributing to quieter operation.

The second option is to mount the outdoor air-conditioning unit on brackets fixed to the wall at a certain height above the ground. And the third and last option is a roof application.

The air conditioner should not be handled after installation. Its components are under pressure and any movement can lead to permanent damage. It is the bracket that can help with the necessary alignment in the future without the risk of damaging the equipment.

Installation of new copper refrigerant line

A new set of copper pipes, consisting of two ducts – a larger (suction) and a smaller (liquid) duct – is used for the air conditioning installation. The suction line is always insulated. The two pipes are supplied together, coiled in a roll of various lengths – usually from 25 to 50 metres. In most homes, 3 to 5 metres will suffice.

The goal is to run the pipe as straight as possible, with a minimum of bends. If necessary, the copper is shaped by hand or with a bender. The pipes are installed alongside the beams and pipes, and it is recommended that they are secured every 1.2 to 1.8 metres using plastic, copper or suitably protected metal bands.

When different metals come into contact, galvanic corrosion, a slow breakdown of the material that can cause refrigerant leakage, can occur. It is therefore important to use a properly insulated fitting.

After preparing the hinges, the plumber first stretches the suction pipe. One end is threaded through the drilled hole (approx. 50-65 mm diameter) towards the outdoor unit. The pipe is secured with slings at the hole and along the route along the beams.

After the suction line is fitted, a smaller, liquid line is run along it and held in the same hinges. The whole system should be free from kinks and sharp handling, the lines being installed as one continuous piece.

A low-voltage control cable is installed along with the cooling line. This conducts the signal from the thermostat to the air conditioner to turn the cooling on and off as needed.

Setting up a new outdoor condenser

After the successful preparation of the bracket, refrigerant lines and wiring, the next phase, the air conditioning assembly of the outdoor unit itself, the condenser, follows. First, the air conditioner is carefully removed from its packaging and mounted on the prepared base. A quality installer will always first check for any damage during transit.

Thorough checks before and after installation are essential. This is the only way to ensure that the air conditioner works reliably right from the start.

Once the air conditioner is installed, the next step is to connect the already installed set of copper refrigerant lines to the service valves on the condenser. These valves serve as a connection point for the system and also allow the refrigerant circuit to be closed for future service interventions. This eliminates the need to refill new refrigerant each time a repair is performed, saving both cost and time.

The joints must then be soldered. This is a process similar to welding, where a combination of oxygen and acetylene and a special filler rod made of a metal alloy with silver is used. The copper pipe and valve are heated to over 650 °C to achieve a strong and leak-proof connection. If this step is done correctly, the connection is durable and airtight, which is crucial for flawless air conditioning operation.

Before filling the air conditioning system with refrigerant, the system must be evacuated. This removes air and moisture from the ducts, which could do a lot of damage to the system. However, this step is usually only carried out in large systems, such as in department stores, warehouses or halls.

Installation of new low voltage distribution lines

For the air conditioning system to be fully functional, the power and control lines need to be professionally connected. As part of the air conditioning installation step, the installer uses the existing power circuit from the main electrical panel in the house and installs a new service disconnect box (called a “disconnect switch”) on the exterior wall.

Inside the disconnect box there are clearly marked terminals for:

Line (inlet) – connection from the house switchboard,

Load (output) – connection of the cable leading to the air conditioning condenser itself.

This interface allows you to quickly and safely disconnect power to the air conditioner during service interventions without the need to turn off the main circuit breaker in the house, which is especially important in emergency situations. Therefore, the disconnector is also required by European and local electrical standards.

The control line is also an important part of the air conditioning system. This line transmits a signal from the control board in the furnace to the air conditioner when the thermostat registers the need for cooling. Proper wiring of this cable allows the unit to respond to changes in indoor temperature and humidity and automatically cycle according to the user’s settings.

The wiring shall be connected to precisely defined terminals.

Commissioning process of the air conditioning system

Once the entire installation is complete, the next important step is to commission the air conditioning system, or test the system. This phase is a crucial part of any air conditioning installation process, as it ensures that all components are working properly and the system is achieving the desired performance.

After switching on, the system must run for at least 15 to 20 minutes to distribute the refrigerant evenly and start an efficient cooling process. It is important that the house is loaded during this testing, i.e. has a sufficiently high indoor temperature, ideally above 24 °C. In some cases, the heating is even switched on briefly to artificially create the required heat load in the house.

This “load” is necessary for the system to operate at full capacity and for the cooling to be accurately adjusted and verified, which includes adding or adjusting the amount of refrigerant.

When commissioning an air conditioner, an experienced technician will check a number of technical parameters to ensure that the system is operating in accordance with the manufacturer’s specifications. This data serves as both a basic diagnostic and a guarantee of proper air conditioning installation. Here is a list of the main data checked:

1. Suction and liquid line pressure

2. Copper pipe temperature – both suction and liquid lines

3. Superheat – the difference between the evaporator outlet temperature and the boiling point of the refrigerant

4. Subcooling – the difference between the condensation point and the temperature of the liquid refrigerant

5. Outdoor temperature

6. Internal temperature

7. Indoor humidity

8. Return air temperature

9. Supply air temperature

10. Static pressure – measured on both the supply and return sides

11. Temperature drop – difference between return and supply air

12. The value of the current drawn

13. Current load of fan motor, outdoor fan and compressor

14. Low voltage line current reading

15. Total length of copper refrigerant piping

16. Amount of refrigerant added – if needed

17. Height difference between outdoor unit and indoor evaporator coil

18. Recorded fan speed (in CFM – cubic feet per minute, converted to m³/h)

Professionally completed air conditioning installation

And it’s done! The air conditioning system is successfully installed, tested and ready to serve you for many years. The process may seem lengthy and technically demanding at first, but in the hands of an experienced installation team, every stage is handled precisely and efficiently. Professional air conditioning installation is not just about wiring the unit, it’s a series of steps that must be done in the right order and with attention to detail.

There is no room for compromise when installing air conditioning. Skipping any of the steps or sloppy workmanship can lead to reduced system efficiency, higher energy bills or even damage to the unit. Investing in an air conditioner is a long-term investment, and proper installation is crucial to its performance and longevity.

How to choose a reliable partner for air conditioning installation?

If you are currently considering a new air conditioner and are looking for a reliable company to install it, we hope this article has provided you with useful information to make your choice easier. At Slovklima, we emphasize a quality installation process and training for our technicians and partners because we believe in getting the job done right the first time.

Are you ready for the next step?

If you need air conditioning for your commercial, warehouse or manufacturing premises, contact us. We will be happy to help you with the selection of a suitable system and with its installation. For small systems, we will be happy to recommend a reliable business partner in your area.

👉 Visit Slovklima.sk and discover a wide range of air conditioners and accessories.