Midea Xtreme Save MSAGDU-24HRFN8 inverter air conditioner 24000 BTU, R32, optional Wi-Fi

Nominal cooling output in British thermal units per hour — the number used to call units 'a 9k', 'a 12k' and so on. 9000 BTU ≈ 2.6 kW, 12000 BTU ≈ 3.5 kW, 18000 BTU ≈ 5.3 kW, 24000 BTU ≈ 7 kW.

How much heat the unit removes from the room under standard conditions, in kW. An inverter can run below and above this figure; the range is given in the note when the maker publishes it.

How much heat the unit delivers to the room in heating mode under standard conditions (+7 °C outdoors), in kW. In hard frost the actual heating output is lower.

The class on the European energy label, calculated from SEER. A+++ is the most economical class on the scale.

The European label class calculated from SCOP for the EU 'average' climate zone, the zone all models are compared in. Classes for the warmer and colder zones, if published, are given in the note.

How many units of cooling the unit delivers, on average, per unit of electricity over the cooling season. The higher the number, the less electricity the same job takes. It is calculated by a single EU method, so it is comparable across brands.

The same for heating: how much heat you get per unit of electricity over the heating season in the 'average' climate zone. SCOP 4 means roughly 4 kWh of heat per 1 kWh of electricity.

Indoor unit sound pressure from the quietest to the top fan speed, dB(A). Around 20–25 dB is a whisper, 35–40 dB a quiet conversation; each +10 dB sounds roughly twice as loud.

Outdoor unit sound power from the EU energy label, dB(A). It is a different measure from the indoor unit's sound pressure: sound power figures are always higher, so compare them only with each other. Matters if the unit hangs near a bedroom window or the neighbours.

An inverter compressor varies its speed smoothly and holds the temperature without abrupt starts and stops. An on/off compressor always runs at full power and stops periodically.

The refrigerant in the system. R32 and R290 have a lower climate impact than R410A; the type matters for servicing and recharging, as the technician must work with that refrigerant.

How much air the fan moves through the unit per hour, from minimum to maximum speed. Higher airflow evens out the temperature faster in a large room; the minimum corresponds to quiet mode.

The lowest outdoor temperature at which the maker allows heating operation. The lower the limit, the longer into winter the unit can be used for heating; in hard frost heating output drops.

Whether a Wi-Fi module for smartphone control is built in. 'Optional' means the module is bought and fitted separately; without it the unit is controlled only by the remote.

What the unit does to the air besides cooling and heating, and how it keeps itself clean, as stated by the maker. Filters trap dust and odours; self-cleaning dries or heats the heat exchanger so mould does not grow inside.

How the louvres move automatically. 'Up-down' swings the airflow vertically, while left-right is set by hand or fixed. 3D moves the louvres in both planes and spreads the air more widely across the room.

Unpacked dimensions from the maker's documentation. Width matters when fitting above a window or door, depth shows how far the unit projects from the wall.

Unpacked outdoor unit dimensions. They matter for a balcony, a niche or a facade bracket.

How far apart the indoor and outdoor units can be along the copper pipe run. A higher value gives more freedom in placing the outdoor unit; a long run may need extra refrigerant.

The supply voltage (and current, if stated) as the maker gives it. It must match your mains or adapter.

The highest total current through the device per the spec sheet. With several channels, their combined load must stay below it.