In brief: Find the right air conditioner by accurately calculating the BTU cooling capacity required for your room size. Choose between portable units for flexibility and split systems for efficiency. Installation often requires a professional, especially for permanently installed models. Regular maintenance with filter cleaning and condensate checks ensures performance and service life.
Buying the right air conditioner: what you need to consider
The market offers a variety of systems. Your choice determines comfort, efficiency and installation effort. First, clarify the intended use: do you need spot cooling or a permanent solution for several rooms?
Portable air conditioners are flexible. You can roll the unit into the room where it is needed and route the exhaust hose through the window. Split air conditioners consist of an indoor unit mounted on the wall or ceiling and a compressor outside the home. They operate more quietly and efficiently.
Multi-split systems use one outdoor unit to cool several indoor units at the same time. They are ideal for an entire floor or a single-family home. The decision depends on your budget and long-term plans.
Sizing the cooling capacity correctly
The capacity of an air conditioner is measured in BTU (British Thermal Units) or kilowatts. A unit with too little capacity struggles against the heat. A unit with too much capacity switches off too quickly and does not dehumidify the room air sufficiently.
Calculate the required capacity based on your room size. A rule of thumb is 60 BTU per square metre. For a room measuring 25 square metres, you need around 15,000 BTU. Also consider the ceiling height, large south-facing windows and internal heat sources such as lighting or electrical appliances.
The biggest mistake is incorrect sizing. Many customers choose an oversized unit because they are afraid of having too little capacity. This leads to short cycles, high air velocity and an uncomfortable indoor climate.
Products such as the drain hoses in our range are useful for correct condensate disposal on many models. The right fittings and threaded connections help with custom line routing.
Professional installation of your air conditioner
Installation determines safety and efficiency. You can set up a portable unit yourself. A split system should be installed by a professional.
Important note
Connecting a split air conditioner to the mains electricity and charging it with refrigerant is regulated by law. This work may only be carried out by a registered electrical contractor and a certified HVAC technician. Mistakes can result in fire, electric shock, damage to the unit and loss of the manufacturer's warranty.
Installing a portable air conditioner: step by step
Place the unit on a level floor near a window. Slide the window kit into the opened window gap. Connect the exhaust hose securely to the unit and the window outlet.
Completely seal all remaining openings around the window. Use sealing tape or foam for this. Every gap allows warm outside air to enter and drastically reduces cooling performance. A suitable
makes this task easier.
Plug the power cord directly into a wall outlet. Avoid power strips or extension cords. The unit draws high current when starting. A dedicated circuit is ideal.
Planning a split system
A professional will inspect your property. They will determine the best location for the outdoor unit. It should be well ventilated, easily accessible and vibration-isolated. The indoor unit is positioned so that cool air can circulate freely throughout the room.
Between the two units, the installer runs two copper pipes for the refrigerant, a condensate drain line and a power cable. This routing requires precise drilling through the exterior wall. The work leaves hardly any visible traces.
Pro tip
It is best to plan the installation of a split air conditioner during the cooler season. Professional installers then have more availability, and you can often get more attractive prices. This ensures the system is ready to use in time for the first hot day.
For all installations, you will find the right accessories here, from shut-off valves to special brass fittings for water systems.
Efficient use and initial start-up
After installation, run a test cycle. For portable units, set the condensate collection tank correctly. With split systems, the technician handles commissioning and adjustment.
Choose a sensible target temperature. A difference of more than six degrees from the outdoor temperature puts strain on the body. 22 to 24 degrees Celsius creates a comfortable indoor climate. Use the timer to start the unit before you arrive.
Keep doors and windows closed while the unit is running. Close curtains or blinds on the sunny side. These simple measures reduce the cooling load and save significant amounts of electricity.
Essential Air Conditioner Maintenance
Regular maintenance keeps performance high, reduces running costs and extends the unit's service life. Neglected maintenance leads to higher energy consumption, poorer air quality and expensive repairs.
The most important task is cleaning the air filters. They trap dust, pollen and hair from the room air. A dirty filter restricts airflow. The fan has to work against resistance, uses more electricity and the unit cools less effectively.
Additional tip
Make a note of maintenance dates in your calendar. Set a regular schedule, for example every four weeks for filter cleaning and once a year for professional servicing. This way, maintenance will not be forgotten and your system will continue to work reliably.
Annual professional servicing
A service technician should inspect your unit once a year. This inspection is particularly important for split systems with a refrigerant circuit. The technician measures the refrigerant pressure and tops it up if necessary.
They clean leaves and dirt from the heat exchanger fins on the outdoor unit. They check that the electrical connections are secure. They inspect the condensate pump and drain to make sure they are clear. A
is ideal for cleaning narrow drain pipes.
Around 80 percent of air conditioner faults could be prevented through simple, regular filter cleaning. Investing in a clean filter pays for itself within a few weeks through the energy saved.
They also check the entire refrigerant circuit for leaks. A slow refrigerant loss often goes unnoticed, but continuously reduces efficiency. The technician records the professional servicing in a report. This report may be required for warranty claims.
Identifying and fixing problems
Your air conditioner is showing signs of a fault. A red warning light comes on or the unit switches off. Simple checks often help before you call customer service.
First check the air filter. Is it dirty? Clean it. Check whether the condensate tank on portable units is full. Empty it. With split systems, check that the outdoor unit is freely accessible and that the fan is turning.
Are you hearing unusual noises? A rattling sound indicates a loose component inside the housing. A whistling or hissing sound may indicate a leak in the refrigerant circuit. In this case, switch the unit off immediately and contact a professional.
A powerful and efficient air conditioner such as the
provides modern comfort for rooms up to 30m². Proper maintenance protects your investment for many years.
Save energy and protect the environment
Modern air conditioners carry the EU energy label. Look for efficiency class A+++ or higher. These units use electricity efficiently and have low running costs.
Combine cooling with other measures. Good overnight ventilation cools the house down in the morning. External shading such as awnings blocks the sun's rays before they reach the windows. Insulation in the roof and facade reduces heat gain in the long term.
Choose a unit with inverter technology. This technology continuously adjusts the compressor's output according to demand. It prevents constant switching on and off, saves energy and improves comfort by maintaining consistent temperatures.
Choosing the right unit, having it professionally installed and maintaining it consistently will make your air conditioner a reliable source of summer comfort. It creates a healthy indoor climate while protecting your wallet and the environment.
Frequently asked questions
- How do I calculate the right cooling capacity for my air conditioner?
- As a rough rule of thumb, allow around 60 BTU per square metre of floor space. For a 20 m² room, you therefore need around 12,000 BTU. Also take factors such as ceiling height, sunlight and heat sources such as computers into account. An undersized unit works inefficiently, while an oversized unit cools the room too quickly and does not dehumidify it properly.
- Can I install a portable air conditioner myself?
- Yes, portable monoblock units are designed for self-installation. The critical step is sealing the window outlet for the exhaust hose. Use the window kit supplied and seal all gaps completely. This prevents warm air from outside from flowing back in and reducing the cooling performance. A stable power supply via a dedicated socket is essential.
- How often do I need to clean my air conditioner's filter?
- Clean the air filter every two to four weeks during intensive use. Under normal operating conditions, cleaning every four to six weeks is sufficient. Remove the filter, vacuum it or rinse it with lukewarm water. Allow it to dry completely before refitting it. A dirty filter reduces airflow, increases energy consumption and can cause unpleasant odours.
- Why is my air conditioner dripping water indoors?
- Water droplets indoors indicate a blocked or incorrectly routed condensate drain hose. The condensation produced during cooling can no longer drain away. Check the drain hose for kinks or dirt. A long, narrow brush is suitable for cleaning it. For permanently installed split systems, this check should form part of the annual professional service.
- What is the difference between a portable and a split air conditioner?
- Portable monoblock units combine the compressor and evaporator in a single wheeled housing. They are easy to install, but noisier and less efficient. Split systems separate the noisy outdoor unit from the quiet indoor unit. They are more powerful, more efficient and suitable for permanently cooling several rooms. However, installation must be carried out professionally by an electrician and a refrigeration engineer.
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