Can you install a heat pump in a Spanish flat? The checks that matter

Decide what the system needs to provide

Replacing a boiler that supplies heating and hot water is a different project from adding cooling or making one room more comfortable. The Spanish term aerotermia refers to air-source heat pump technology. It can include air-to-water and air-to-air systems, which deliver heat differently and do not necessarily provide the same services. Ask the installer to state exactly what the proposed installation will do.

Prepare details of the flat's area, location, orientation, windows, insulation and usual occupancy. If you have energy records, include the periods covered and whether they include heating, cooling, hot water or other uses. Floor area helps establish a starting point, but multiplying it by a fixed number is not enough to select the final output. The installer should explain the sizing and the operating conditions used in the assessment.

Official source: IDAE · La bomba de calor en la rehabilitación energética de edificios

Allow room for installation and maintenance

The outdoor unit needs the manufacturer's specified clearances, suitable airflow, maintenance access and provision for water drainage where required. Have the proposed position assessed for noise and vibration, the route of the connections and the effect on neighbours. A balcony space is only usable if these conditions can be met.

If hot water storage is part of the design, allow room for the cylinder, its connections and servicing. A cupboard's full internal volume is not all available for equipment. Check the actual components on the design, such as pumps, valves and controls, because systems differ. Have the electrical supply and any required electrical alterations assessed too.

In Spain, work affecting the façade, roof or other shared parts of a building may involve the comunidad de propietarios, the owners' association. Ask the professional assessing the installation and the association which approvals are needed, and check the applicable municipal procedure separately. Permission from the association does not automatically satisfy the council's requirements, or the other way round.

Official source: Ajuntament de Barcelona · Consulta prèvia d’obres

Have the radiators assessed room by room

You may be able to keep existing radiators, but that decision needs a calculation. For each room, compare the heat required with what the radiator can deliver at the water temperature proposed for the new system. A radiator designed for other operating conditions may need adapting or replacing; it should not be removed automatically without that assessment.

If you also want cooling, do not assume conventional radiators will provide it. The system needs suitable equipment and controls, with condensation management where relevant. Ask how heating and cooling will reach each room so that the proposal describes the result you can expect throughout the flat.

Compare complete installations for the same brief

Ask for an option that reuses suitable parts of the existing installation and another that includes the alterations needed for your preferred result. Make the differences explicit: what each system provides, the work it requires and any limitations it leaves. A cheaper option may be useful, provided you understand what it will and will not do.

For energy savings estimates, ask to see the assumed demand, water flow temperature where applicable, performance, climate, tariff and usage. Check whether every option covers the same services. An annual savings figure is difficult to judge if one calculation includes hot water and another leaves it out.

Reconsider the system if the flat cannot accommodate it

If there is no suitable equipment location, necessary work cannot be authorised or the alterations exceed the budget, review the approach before choosing a unit. Improving the walls or windows, treating individual rooms or combining systems may be alternatives worth assessing. The comparison should return to what the flat needs, rather than simply substituting a different brand.

If you already have a heat pump that performs poorly, ask a professional to inspect the controls, radiators or other indoor units, flow rates and condition of the installation before replacing the machine. Record when the problem occurs and which rooms are affected. A larger or newer unit may leave the same fault unresolved if its cause lies elsewhere in the system.