Modern air source heat pumps (ASHPs) are a leading choice among those who want to heat and cool their homes efficiently and effectively.
This system extracts heat from the air outside, even in low temperatures, in order to deliver it indoors, with minimal energy use.
Finding the best model to meet the needs of a specific home and choosing a brand that is sturdy and durable are essential to getting the most out of this investment.
What to look for in an air source heat pump
There are certain basic features that are worth reviewing when choosing: key efficiency metrics, noise levels, warranty, additional smart features, and installation compatibility with other systems.
Key efficiency metrics: SCOP, COP, and seasonal performance
There are two key technical performance and efficiency metrics: SCOP (Seasonal Coefficient of Performance) and COP (Coefficient of Performance).
- COP indicates the heat output / electrical input ratio under specific conditions. For example, a COP of 4 would mean the unit produces four units of heat for every unit of electricity consumed.
- SCOP is similar, but it is focused on providing more accurate and realistic data, applying COP to varying temperatures to get an average coefficient. In cooling mode, efficiency is usually expressed with SEER (Seasonal Energy Efficiency Ratio) or HSPF (Heating Seasonal Performance Factor).
Noise levels, warranty, and smart features
Noise levels are crucial for comfort. Modern ASHPs usually operate with low noise levels, but it is important to notice them when choosing where to install outdoor units.
As for the warranty, each air source heat pump manufacturer offers a different period, often starting from 5 years.
Smart features can be useful to save energy and can also be particularly convenient. Wi-Fi connectivity, smart thermostats and adaptive inverter compressor technology are great to integrate with home automation.
Installation compatibility with heating systems
If you already have a heating system, such as underfloor heating or radiators, it is important to check if an ASHP is compatible with them.
Air source heat pump comparison
How to compare between different ASHP models?
Residential vs commercial units
Residential ASHPs typically offer heating capacities from 4 to 16 kW, and are suitable for single-family homes.
Commercial ASHP models can exceed 30 kW, which supports multi-residential buildings or large offices. These often come with advanced features, such as integrated backup heaters.
Ideal brands for different property types
Most brands, such as Saunier-Duval, Mitsubishi, Fujitsu and Daikin, are suitable both for small and large homes and apartments while commercial applications usually require specific brands and models. Make sure there are installers and maintenance providers available in your area.
Cost vs performance
Higher SCOP units may cost more upfront but will save more in long-term energy bills. When the budget is tight, balance efficiency with warranty and local service coverage, which might be key in the long run.
Air source heat pump ratings explained
How do energy ratings work and how important are them when comparing ASHPs?
How ratings work
In Spain and the rest of the EU energy labels grade ASHPs from A to G. An A rating represents the highest efficiency achievable, while G is the lowest.
The energy rating label also includes other information, like SCOP, SEER, noise levels, and sometimes a climate-specific rating.
Manufacturers often provide additional technical data, including defrost cycle performance, which are important for cold climate installations.
Efficiency in cold weather vs mild climates
Low-temperature ASHPs can still operate efficiently at below zero temperatures, but performance indicators drop as outdoor temperature decreases. In mild climates, however, efficiency stays high all year.
Reading manufacturer vs real-world performance data
Manufacturer data is usually tested under controlled conditions, which means real results may vary depending on several conditions, such as the quality of the installation, system sizing and overall building insulation.
Air source heat pump vs air conditioner
What are the differences between an ASHP and air conditioner?
Functionality and energy consumption
While both systems use refrigerant, reversible heat pumps can heat and cool spaces, while air conditioners are designed just to cool areas. This means heat pumps are more efficient and minimise the need for two different systems.
Heating capabilities in winter
Unlike standard air conditioners, ASHPs are optimized to provide heating in sub-zero conditions, with defrost cycles preventing frost build-up on the outdoor units.
Long-term cost and maintenance
Both the equipment and installation of air conditioners may be more economical, but heat pumps are more efficient and can replace both heating and cooling systems, thus minimizing costs. Maintenance is similar for both.
Best air source heat pumps for underfloor heating
If you are looking for an ASHP for underfloor heating, you must acknowledge different features.
Temperature requirements and system compatibility
Underfloor heating (UFH) uses hot water running through pipes under the floor. The water is normally between 30 and 45ºC, depending on the temperature set.
Low-flow temperature heat pumps are ideal for this heating system, as they offer high efficiency at lower temperatures.
Recommended brands and models for low-flow systems
In a Mediterranean climate, some recommended models, compatible with UFH are Vaillant aroTHERM plus or Mitsubishi Ecodan Low Temp.
Pros and cons compared to radiators
Pros: Lower costs, even heat distribution, compatibility with renewable energy.
Cons: Slower heat-up time, requires insulation.
Final considerations when choosing a heat pump for your home
We evaluate your space to recommend the most suitable heat pump setup. Choosing the right air source heat pump requires considering many features and factors. It is an important investment for your home, so it is advisable to lean on expert knowledge.
