ASHP myths & misconceptions
Air Source Heat Pumps (ASHPs) have gained popularity as a low-carbon alternative to traditional heating systems. However, several myths and misconceptions persist, often deterring homeowners and developers from making the switch. Let’s set the record straight by addressing the most common misconceptions:
Inefficient in Cold Climates
While early models of air source heat pumps had limitations in extremely cold temperatures, modern systems are designed to operate efficiently even at temperatures as low as -25°C.
This is possible because there is still usable heat energy in the air, even in sub-zero conditions.
Technologies such as inverter-driven compressors, enhanced defrost cycles, and smart controls ensure consistent performance year-round.
In fact, air source heat pumps are widely used in Scandinavian countries, where winters are much colder than in the UK, clear proof of their cold-weather capability.
In reality, if a heat pump is struggling to maintain indoor temperatures in winter, it is rarely the fault of the heat pump itself.
More often, the issue lies with poor system design, incorrect sizing, or maintenance problems, for example, a blocked filter or other minor fault preventing the system from operating at full efficiency.
Expensive to Install and Run
It’s true that air source heat pumps have a higher upfront cost compared to traditional gas boilers or electric heaters.
However, when you factor in government grants and incentives, the net cost often comes close to that of a boiler replacement, especially for eligible households.
Over time, the slightly higher initial investment is typically offset by lower running costs, resulting in a strong return on investment.
These savings are even greater when air source heat pumps are powered using heat pump-specific tariffs or paired with battery storage systems that charge overnight using cheaper off-peak electricity.
Additionally, air source heat pumps tend to have a longer lifespan than gas boilers.
Fossil fuel systems experience more wear and tear due to repeated high-temperature cycles, whereas heat pumps operate at lower, more consistent temperatures, leading to reduced mechanical stress and longer service life.
Air Source Heat Pumps Are Too Noisy
The Reality: While some older or lower-quality models can be slightly noisier, advancements in compressor and refrigerant technology have significantly reduced operational noise levels in modern systems.
Today’s air source heat pumps typically operate at around 54 decibels, roughly equivalent to a quiet conversation or light rainfall.
With careful installation and thoughtful placement, such as positioning the unit further down the garden or away from windows, any audible disturbance can be further minimised.
In many cases, the noise becomes virtually imperceptible, especially when the heat pump is correctly specified and installed for the property.
Heat Pumps Always Need a Backup Heating System
While a backup heat source may be advisable in extreme or prolonged sub-zero climates, a well-designed air source heat pump system is often more than capable of meeting all a home’s heating needs on its own.
When working with an MCS Certified designer, a detailed heat loss calculation is carried out to ensure the chosen heat pump is accurately sized for your property.
This eliminates the need for regular reliance on an electric backup, ensuring consistent comfort and efficient operation even in colder months.
The only exception is in some low-temperature R32 systems, where an electric immersion heater may be used occasionally to raise hot water temperature by 10°C for legionella prevention.
However, even this can be avoided by choosing a high-temperature heat pump, such as those using R290 refrigerant, which can perform a full bacteria purge to 60°C without any electrical assistance.
Another myth, busted!
Not Environmentally Friendly
While it’s true that air source heat pumps require electricity to operate the fan and compressor, the systems themselves do not burn fuel or release carbon emissions directly.
In contrast, fossil fuel boilers emit CO₂ and NO₂ into the atmosphere every time they run.
The sustainability of a heat pump increases significantly when it’s powered by renewable electricity.
Homeowners can choose green energy tariffs from suppliers that prioritise wind, solar, or hydro sources, effectively making their heat pump a fully renewable heating solution.
More importantly, using electricity for heating opens the door to other green technologies like solar PV panels, battery storage, and off-peak tariffs, allowing homeowners to further reduce energy bills and environmental impact, something not possible with gas or oil systems.
Difficult to Maintain
The Reality: Like any heating system, air source heat pumps require routine maintenance to ensure optimal performance.
This includes cleaning filters, checking refrigerant levels, and inspecting system components, simple tasks that help maintain efficiency and extend the life of the unit.
When issues do arise, they’re rarely due to the heat pump itself, and more often the result of poor initial design, incorrect sizing, or substandard installation.
These oversights can place unnecessary strain on the system, leading to premature wear and reduced reliability.
Choosing a qualified, MCS Certified installer ensures that your heat pump is designed, installed, and commissioned correctly, reducing the likelihood of breakdowns and giving you a long-lasting, low-maintenance system.
Heat Pumps Don’t Have Enough Power to Heat Larger Properties
The Reality: It’s true that heat pumps typically deliver lower kilowatt outputs compared to traditional gas boilers, which are often oversized and rarely operate at full capacity, especially in modern homes with improved insulation and airtightness.
However, this does not mean heat pumps are underpowered or unsuitable for larger properties.
Modern air source heat pumps come in a wide range of sizes and capacities, including three-phase models for higher demands.
In fact, many manufacturers offer the ability to cascade multiple heat pumps, allowing them to work together in tandem to efficiently heat large homes or commercial buildings without compromising comfort.
With correct sizing and design, heat pumps can easily handle the heating and hot water demands of everything from compact flats to sprawling country homes and multi-zone commercial buildings, all while reducing carbon emissions and energy costs.
Conclusion: Busting Myths, Embracing the Future
Air source heat pumps are a proven, efficient, and environmentally friendly solution for modern heating and hot water needs.
By dispelling these common myths, we hope to empower homeowners and industry professionals to make informed, confident decisions that support both long-term savings and a more sustainable future.
- Lower running costs
- Reduced carbon emissions
- Reliable performance, even in winter
- Flexible design for all property types
Join the renewable revolution – take control of your energy, reduce your environmental impact, and future-proof your home with the power of air source heat pumps.
