Choosing and installing air conditioning (aire acondicionado)

Terms used

• Comunidad de propietarios — The comunidad de propietarios is the owners' association of a building, which decides on shared parts such as facades and roofs.
• Ordenanza — An ordenanza is a local rule set by your town hall, for example on outdoor units, noise and drainage.
• Frigorías — Frigorías are the unit Spanish sellers use for cooling power; one kW is about 860 frigorías.
• SEER — SEER is the seasonal efficiency rating for cooling; a higher number means less electricity used.
• SCOP — SCOP is the seasonal efficiency rating for heating; a higher number means less electricity used.

Key rules

• Community consent: A unit on a facade, roof or other shared part generally needs the owners' approval.
• Installer: Use a registered installer company with an F-gas certified technician, and get an installation certificate.
• Town hall rules: Check your local ordinance on outdoor unit position, noise and condensate before ordering.
• Size: Do not oversize: a unit that is too big cycles on and off and leaves the air damp.

What you need before you buy

You can install air conditioning legally when four things line up: your community agrees (if the unit touches common parts), your town hall's rules are met, a certified installer does the work, and the unit suits your home. Sort the first two before you pay anyone.

If you rent, ask your landlord for written permission first.

Community consent

If the outdoor unit goes on a facade, roof or other shared part of the building, you generally need approval from the comunidad de propietarios (the owners' community). Many communities vote on it at the owners' meeting.

• A change that alters the look of the facade usually needs a three-fifths vote of owners. Some energy-saving works need only a simple majority.
• A unit on your own private terrace may not need a vote. That changes if the community statutes forbid it or the unit changes how the facade looks.
• Read the statutes and any earlier agreements, and ask the administrator before you order.

Town hall rules

Each town hall sets its own rules in an ordenanza (local ordinance). Check yours, because limits and permit needs differ by city. Typical rules:

• Outdoor units are often barred from street-facing facades, or must be hidden on a roof, patio, courtyard or behind a lattice.
• Noise limits apply at neighbouring homes. At night they are often around 25-30 dB(A) indoors and 45-55 dB(A) outdoors, depending on the zone.
• Condensate (the water the unit produces) must go to a drain or be collected. It cannot drip onto the street or onto neighbours.
• Units usually need a minimum height above the pavement, often about 2.5 m.
• Historic centres and protected buildings are stricter.

The installer

Only a registered company can fit a split system. It must be registered as an installer of thermal installations with the regional industry department. The person handling refrigerant also needs a personal fluorinated gas (F-gas) certificate.

Ask for both before you accept a quote. After the work, the installer issues the installation certificate and, where required, registers it with the region. Keep that certificate and an invoice with warranty. Requirements for registration and project papers vary by power and region.

Sizing the unit

A rough guide is about 1 kW of cooling for every 8-10 m² of an ordinary room. In Spanish sales talk this appears as frigorías: about 100-150 per m². One kW is about 860 frigorías.

Go higher for a top-floor flat, large south or west windows, poor insulation, a kitchen or many people. Go lower for a well-insulated, shaded home. A technician's heat-load calculation beats any rule of thumb.

Do not oversize. A unit that is too big switches on and off constantly and leaves the air damp. Inverter units cope better with imperfect sizing.

Efficiency and the energy label

Every air conditioner under 12 kW carries an EU energy label. Cooling efficiency is shown as SEER and heating efficiency as SCOP. Higher numbers mean less electricity for the same comfort. Classes run from A+++ (best) to D. The label also shows yearly kWh use, sound level in dB and capacity in kW. Spain mostly falls under the average or warmer heating zone. Choose a heat pump (a unit that also heats) if you want one machine for winter and summer. A newer label scale is being prepared, so classes may change.

What it costs

A single split for a normal room generally costs from several hundred euros to around a couple of thousand, depending on capacity, brand, inverter or Wi-Fi features, and pipe length. Multi-split systems with two to four indoor units cost considerably more. Ducted systems cost more still.

Installation is usually a fixed fee plus extras such as extra pipe, a condensate pump, wall drilling or crane access. Summer is dearer and slower. Get several written quotes that include the installation certificate and warranty.

The documents, checklist and questions below cover the paperwork and the practical details.

Documents you need

• The installer company's registration as a thermal-installations installer, issued by the regional industry department.

• The installer's personal fluorinated gas (F-gas) certificate, which covers work with refrigerant.

• The installation certificate, issued by the installer after the work and registered with the region where required.

• An invoice with warranty, and a written quote that includes the installation certificate.

Which documents are needed can change with the system's power and your region, so confirm with your installer or regional industry department.

Checklist

• Check your town hall's ordinance for rules on outdoor units, noise, drainage and minimum height above the pavement.

• Ask whether your building is in a historic centre or protected area, where rules are stricter.

• Ask the installer for proof of company registration and their F-gas certificate.

• Confirm the condensate will be piped to a drain, not left to drip.

• Ask for the installation certificate and an invoice with warranty when the work is done.

Frequently asked questions

Can I put the outdoor unit on my private terrace without a vote?

Often yes, if the terrace is private, your community statutes do not forbid it and the unit does not change how the facade looks. If it is visible from the street or alters the facade, you usually need a three-fifths vote of owners. Read the statutes and ask your administrator before you buy.

How much noise is my outdoor AC unit allowed to make?

Night-time limits are often around 25-30 dB(A) inside neighbouring homes and about 45-55 dB(A) outside, depending on your zone. Your city's noise ordinance sets the exact figure. Check the sound power on the energy label before buying.

Where can the condensate water from my AC go?

Condensate must not drip onto the street or onto neighbours. It has to be piped to a drain or collected, and many cities ban free dripping onto pavements. Ask your installer to include the drain pipe in the quote.

How big should my AC unit be for a 20 m2 room?

A rough rule is about 1 kW of cooling per 8-10 m2, so a 20 m2 room needs around 2-2.5 kW. Add capacity for a top floor, big south or west windows or poor insulation. A technician's heat-load calculation is better than the rule, and oversizing causes short cycling and humidity.