Not below 24 °C
More than six to eight degrees below the outside temperature feels unpleasant to most people. 24 to 26 degrees is almost always enough.
Guide
Practical guide
Answers to the questions customers in Luxembourg ask us most often.
Seven rules for everyday use
Never aim the airflow at people
Point the louvres upwards. Cold air sinks on its own and spreads more evenly.
Windows closed
A tilted window can double consumption. Ventilate early in the morning and late in the evening.
Shade before you cool
External shading cuts the cooling load far more than any control setting. Internal blinds help only a little.
Use night mode
Silent or sleep mode reduces fan speed and slowly raises the target temperature.
Avoid constant on-off
Inverters are most efficient running continuously at low output, not in stop-and-go.
Let the dry function run on
The evaporator dries out and odours never get started.
Frequently asked questions
Can I install air conditioning in a rented flat?
For a fixed split system you need the owner's written consent, because work is done on the façade and the wall. In a condominium a resolution of the owners' meeting is needed too. Without consent, only a portable unit remains.
How far from the neighbour must the outdoor unit be?
There is no single distance in metres; noise protection and communal building rules decide. In practice, at least two metres from the boundary, facing away from neighbouring windows and mounted on anti-vibration pads works well. Talking to neighbours early saves a lot of trouble.
How long does an air conditioner last?
With annual servicing, 15 to 20 years is realistic. Without servicing the life drops sharply and the compressor – the most expensive component – usually goes first.
Is air conditioning bad for the environment?
The footprint comes mostly from poor use. An efficient unit with R32 or R290, cleanly installed, run on green or self-generated electricity and used for heating in winter has a far better balance than a portable unit plus a gas boiler.
Can I install it myself?
Quick-connect kits exist, but work on the refrigerant circuit requires a certificate of competence in the EU. Without evacuation, moisture stays in the circuit and destroys the compressor. Warranty claims usually lapse as well.
What is the difference between BTU and kW?
Both describe cooling capacity. 12,000 BTU per hour is about 3.5 kW, 9,000 BTU about 2.6 kW. Manufacturers mainly use BTU in model names such as 9k, 12k or 18k.
Do I need a bigger electricity connection?
For one or two indoor units, usually not. With a large multi-split alongside a wallbox and a heat pump, it is worth checking the house connection rating.
Five mistakes that get expensive later
First, choosing capacity by gut feeling. Second, putting the outdoor unit in a tight recess or courtyard where heat builds up. Third, skipping evacuation during installation. Fourth, saving on servicing and losing the manufacturer's guarantee. Fifth, accepting the cheapest quote without a detailed scope – brackets, condensate pump, trunking and electrics are usually the items missing from it.
The right setting saves real money
The most common mistake is diving straight to the bottom: 18 degrees does not cool faster, it cools for longer and costs more. Six to eight degrees below the outside temperature is sensible, so usually 24 to 26 degrees in high summer.
Let the system run rather than switching it on and off constantly. An inverter is most efficient in quiet part-load operation; every cold start costs more than continuous running would have saved.
- Six to eight degrees below the outside air
- Run continuously instead of frequent cycling
- Night mode cuts both noise and consumption
Still have a question?
Write to us. We answer even when it does not turn into a job.