Yes, an air conditioner can certainly work without a traditional outdoor unit. Monoblock air conditioners are an innovative solution where all components are integrated into a single indoor unit. These systems use air ducts through the wall to dissipate heat, meaning you do not need to install a visible outdoor unit on your facade.

Why does a visible outdoor unit cause problems for monumental buildings?

With monumental buildings and apartments with a Homeowners' Association (VvE), you often run into strict regulations. A traditional split air conditioner requires a conspicuous outdoor unit that can disrupt the historic appearance of your property. This means lengthy procedures for permission, possible rejection of your application, and hassle with neighbors who object to the visual impact. The result? Delays lasting months and sometimes no air conditioning at all, while summer is already over. With a monoblock system, you change virtually nothing to the exterior facade, meaning you often do not need additional permission and can immediately enjoy a comfortable indoor climate.

How does a lack of space limit your air conditioning choices more than you think?

Many people do not realize that their limited wall space drastically restricts their air conditioning options. Traditional systems often require a lot of space for both indoor and outdoor units, plus clearance around them for maintenance. In narrow bay windows, between windows, or in small bedrooms, this quickly becomes an unsolvable puzzle. The result is that you either choose a system that is too small and does not cool effectively, or you cannot install air conditioning at all. Modern monoblock systems, however, offer compact solutions, such as vertical models just 50 cm wide or mini versions with a depth of only 16,5 cm, allowing you to cool optimally even in tight spaces.

Can an air conditioner really work without an outdoor unit?

Absolutely! Monoblock air conditioners prove that effective cooling is possible without a visible outdoor unit. These systems integrate all components into a single indoor unit and use air ducts through the wall for heat dissipation.

The operating principle is ingeniously simple. The monoblock unit draws in warm indoor air, cools it down via a built-in cooling system, and blows the cooled air back into the room. Simultaneously, the warm air is vented outside through a duct, while fresh outside air is drawn in for cooling. This is all accomplished through two holes in the wall covered with discreet facade grilles.

The performance is comparable to traditional split systems. Modern monoblock units can effectively cool rooms up to 48 m² and remove up to 15 liters of moisture per day from the air in high humidity. They also offer the advantage of heating in winter, although effectiveness decreases at temperatures below 5°C.

What are the alternatives to a traditional split air conditioner?

There are various alternatives, each offering its own benefits, depending on your specific situation and wishes.

Monoblock air conditioners form the most advanced alternative. These systems are available in various versions:

Horizontal models (55 cm high, 101 cm wide) for standard wall mounting
Vertical versions (140 cm high, 50 cm wide) perfect for narrow spaces
Ceiling models for optimal space utilization
Mini versions (16,5 cm deep) for small bedrooms

Mobile air conditioners They offer flexibility because you can move them between rooms. However, they do require a hose to the outside for heat dissipation, which limits mobility. The advantage is that you do not need a permanent installation.

Window air conditioners They are mounted in the window and are popular in countries such as America. In the Netherlands, they are less common due to our window constructions, but they can be an option with suitable windows.

Evaporative coolers They use water evaporation for cooling and are energy-efficient, but only work effectively in dry climates. They are less suitable for the humid summers in the Netherlands.

How does a portable air conditioner without a fixed outdoor unit work?

Portable air conditioners are essentially a smart variation on the monoblock principle, where all components are housed in a wheeled unit.

The system works via a flexible exhaust hose that you route outside through a window, door, or a special opening. The mobile unit cools the indoor air and expels the warm air outside through this hose. Some models have one hose (exhaust only), while others have two hoses (exhaust and intake) for better efficiency.

The advantages of mobile units are clear:

No permanent installation required
Movable between rooms
Relatively cheap to purchase
Suitable for rental homes

However, there are also disadvantages. Portable air conditioners are often less efficient than fixed systems, produce more noise, and the exhaust hose must be properly sealed to prevent warm air from flowing back. Furthermore, they take up floor space and you have to empty the condensate water regularly.

However, for temporary cooling or in situations where a permanent installation is not possible, mobile units offer a practical solution without the need to drill holes in walls.

When do you need concrete drills for air conditioning installation?

Concrete drilling becomes essential when you want to install a monoblock air conditioner in buildings with concrete walls, which is very common in the Netherlands in new construction projects, office buildings, and many apartment complexes.

For monoblock systems, two holes with a diameter between 160 and 200 millimeters are required. These holes ensure air circulation: one for the extraction of warm air and one for the supply of fresh outside air. With concrete walls, this requires specialized work because concrete is much harder than stone and requires different drilling techniques.

Drilling into concrete is performed using water-cooled diamond core drills to prevent overheating and create a clean, round passage. This is crucial because the air ducts must align perfectly to ensure efficient operation and good insulation.

Other situations where concrete drilling is necessary:

Installation on upper floors in concrete apartment buildings
Penetrations through reinforced concrete (with steel reinforcement)
More complex installations, such as roof penetrations for pitched roofs.
Situations where condensate drainage is also desired

Professional concrete drilling ensures that the installation proceeds smoothly without damage to the structure and that the air conditioning system functions optimally.

How De Betonboorder helps with air conditioning installation

We specialize in professionally drilling the necessary holes for monoblock air conditioners and ensure a flawless installation from start to finish. Our experience with all types of walls and situations makes the difference between a perfect installation and problems afterwards.

What we arrange for you:

Precision drilling of air ducts with diamond core drills for an optimal fit
Protection of walls and floors during drilling
Optional condensate drain at no extra cost
Installation on any desired floor
Leaving the workplace tidy
Delivery within 3 weeks subject to availability

Whether you want a horizontal, vertical, or ceiling unit, we provide the perfect cable entries so that your new air conditioner can perform optimally. Contact us for a no-obligation quote and soon enjoy a comfortable indoor climate without a visible outdoor unit.

Can an air conditioner work without an outdoor unit?