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Air conditioning for flats: capacity and noise level
Sizing air conditioning by eye is the most common mistake I see in flats across Brno: either the unit is unnecessarily oversized or it barely keeps up in summer.
How to calculate capacity based on square metres
A basic guideline for an apartment with standard ceiling height and no extensive glazing is approximately 100 W of cooling capacity per square metre. For a room facing south or west with large windows, it is sensible to add a margin as it heats up more during the day. For a typical bedroom of around 20 m², this results in a unit of about 2.5 kW, while for a living room with kitchen of around 35 m², it is closer to 3.5 kW. It is better to have the exact figure calculated during the survey, as factors such as the number of people in the room, window orientation and high-performance electronics commonly used in the room also play a role.
Panel building or brick house, this also affects the required output capacity.
Flats in panel buildings on estates in Bystrce or Líše are usually well thermally insulated from the factory, especially after facade revitalisation, so they often require lower capacity than would correspond to the tabulated area. Flats in older brick houses in the centre tend to have high ceilings and older windows that retain cold less effectively, there I prefer to add a reserve to the basic calculation. That is precisely why it makes sense to have the capacity calculated on site, not just according to an internet formula.
Where to place the unit in the room
The ideal location is above the door or on a free wall opposite the window, allowing airflow to pass through the entire room without blowing directly onto the bed or work desk. In smaller flats where almost every wall is occupied by furniture, we seek a compromise during the survey, sometimes moving the unit half a metre to the side makes a noticeable difference in comfort.
Split or multisplit
Split means one outdoor and one indoor unit: a solution for a single room or smaller flat. Multisplit has one outdoor unit with several indoor units connected to it at once. It pays off where you want to air-condition two to four rooms and do not want several outdoor units side by side on the façade. This is especially appreciated by flat owners in panel buildings, where the building's owners' association decides how many units the façade can support. The disadvantage of multisplit is that if the outdoor unit fails, all connected rooms stop cooling at once, not just one.
Questions to ask about noise levels
Indoor units are practically inaudible in quiet night mode; the outdoor unit makes the main difference. In apartment blocks in Líšeň or Bystrc, where neighbours' windows are only a few metres away, I choose quieter models and position them away from bedroom windows to avoid disturbing anyone's sleep. In brick houses closer to the centre, where flats are nearer the street, noise from the street is often a bigger problem than the air conditioning itself, this should also be considered when selecting the location for the indoor unit.
How many units for a larger flat
Recently, for a new build in Vinohrady, we installed a multi-split system for three rooms: the living room, bedroom and study, connected to a single outdoor unit on the building's roof. In a detached house in Komín, it was just one standalone wall-mounted unit for the living room, as there was no need to cool the rest of the house. Before deciding on multiple units at once, work out with the installer whether a multi-split is actually cost-effective or if you are better off with a single well-positioned split unit for the room where it really gets hot.
Inverters are now the standard.
The vast majority of modern split units operate with an inverter: the compressor does not run at full capacity and then switch off completely, but smoothly adjusts its speed according to how much cooling the room requires at any given moment. The result is quieter operation, smaller temperature fluctuations in the room, and lower electricity consumption compared to older units without an inverter.
Brands we install
I most often install Daikin, Samsung and LG units, for all three I can source spare parts and service even years later. Air conditioning including turnkey installation for these brands starts from 28 000 Kč, but we prefer to discuss the exact price based on capacity and model during a personal survey, where I will show you the differences between models, energy consumption and the appearance of the indoor unit.
A complete overview of installation prices is available in the article about Installation of air conditioning in Brno and its progressIf you are dealing with an apartment in a panel building, also read Installation specifics for apartment blocks - consent from the building's owners' association, placement on the façade and core drilling.
Would you like a non-binding quote for air conditioning?
Write a few sentences about your flat or house and I will get back to you with a specific amount. Or just call me directly; I take calls at weekends too.