External Units

What is the outdoor unit of an air conditioner?

The outdoor unit, also called the compressor or outdoor section, is the component installed outside the home that runs the entire air conditioner. It houses the compressor and manages heat exchange with the air: it cools in summer and, thanks to the inverter heat pump, heats in winter. Every system, whether monosplit or multisplit, needs a correctly sized outdoor unit.

How to choose the outdoor unit's capacity

Capacity is measured in BTU and is chosen according to the indoor units the outdoor unit has to power. Our catalogue offers 190 outdoor units, with capacities distributed as follows:

• 9000 and 12000 BTU: the most common sizes, ideal for monosplit systems serving a single room.
• 18000 and 24000 BTU: for large rooms or for small two-unit multisplit systems.
• 30000, 36000 and 48000 BTU: for systems with three or four indoor units.
• 60000 BTU: for the largest configurations, such as the penta split systems of villas and homes with many rooms.

Single outdoor unit or multisplit?

An outdoor unit for a monosplit system powers a single indoor unit and is the right choice when you need to air-condition one room. A multisplit outdoor unit, on the other hand, has several connections and serves from two up to five indoor units with a single outdoor section. If you're planning a system for several rooms, start from the multisplit configurator and then choose the suitable outdoor unit.

Compatibility with the indoor units

The basic rule is simple: add up the BTU of all the indoor units you want to connect and choose an outdoor unit able to power them, leaving a small margin since they rarely all run at full capacity together. Always check the number of connections on the outdoor section and that the brand of the outdoor unit matches that of the indoor units, because a Daikin outdoor unit must be paired with Daikin indoor units, and so on for each manufacturer. You can connect different types, such as wall units and cassette units.

Where to install the outdoor unit

The position of the outdoor unit affects the system's performance and lifespan. Here are the main criteria to follow:

• Choose a ventilated spot, where air circulates freely and isn't trapped.
• Avoid direct, prolonged sun exposure during the hottest hours, because it lowers efficiency.
• Leave enough space around the unit for maintenance and condensate drainage.
• Limit the distance from the indoor units, to reduce losses and installation costs.
• Fix the unit on sturdy brackets, on the wall or on the ground, to contain vibration and noise.

The best brands available

You'll find outdoor units from the sector's leading manufacturers, with official warranty and available spare parts: Mitsubishi Electric with 28 models, Daikin with 22 models, Hisense, Haier, Fujitsu, LG, Midea, Panasonic and Samsung. Prices start at around 112 euros for the most compact units and reach the most powerful solutions for large systems.

Consumption and efficiency

A quality unit with inverter technology modulates its capacity instead of switching on and off continuously, and this clearly reduces consumption. Cooling efficiency is read from the SEER value, heating efficiency from the SCOP: the higher these ratings, the lower the bill. You'll often find dedicated promotions in the offers section, with the most sought-after brands in stock.

Frequently asked questions