The Incredible Efficiency,Benefits Of Air Source Heat Pumps

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By Debarghya Roy

Air Source Heat Pump COP (ASHP COP) provides an important clue into understanding the energy performance of this particular heating system. 

In this blog post, we will explore what ASHP COP is, why it matters, and how it affects air source heat pump efficiency in different climates and temperatures around the world.

Key Takeaways

  • Air Source Heat Pump COP (ASHP COP) is a measure of the efficiency of an air source heat pump, indicating how much heat is produced for each unit of electricity consumed by the system.
  • Seasonal Performance Factor (SPF), which takes into account external temperature and humidity levels, affects ASHP’s coefficient of performance.
  • Optimizing installation setup plays an equally significant role towards achieving desirable performance rates with different types of heating systems like air or ground source pumps.
  • Ideal range for optimal efficiency in ASHPs typically lies between 2 – 4, while higher grades may achieve ratings up to 6 depending on location preference and climate conditions present during installation & operation times.

Definition Of COP 

Air Source Heat Pumps

COP, an acronym for “coefficient of performance,” is a key factor when measuring energy efficiency in heat pumps, air conditioners and refrigerators. 

The COP (Coefficient of Performance) is a measure of the efficiency of a heat pump, representing the ratio between useful heat energy generated by the heat pump and its energy input.

In the case of air source heat pumps, or ASHPs, this is referred to as Air Source Heat Pump COP (ASHP COP).

Calculation Of COP Of Air Source Heat Pump

The ratio of cooling power extracted from the device and power supplied to it denotes the Air Source Heat Pump’s specific coefficient of performance

This concise formula makes calculating heat pump efficiency simple: 

Dividing total heating capacity (or cooling work) generated by the amount of electricity absorbed by the unit; 

c = q/p 


c stands for coefficient, 

q is the rate at which heat generated given off 

p represents the amount of power needed to drive the whole process i.e actual energy used up during the process.

How Does The COP Affect The Energy Efficiency Of Air Source Heat Pump?

A sophisticated air-to-water type pump can achieve COPs as high as 4 or more depending on seasonal performance factor (SPF).

SPF takes into account varying climate conditions like external temperatures and humidity levels which also affects air source heat pump performance. 

For example, when ambient temperature goes below 9°C then COP may suffer significantly due to pressure drop from low boiling point refrigerants used in closed loop systems; this indicates that selecting proper refrigerant for specific climate should be taken into consideration when installing such a system.

Higher values indicate an efficient unit operating at optimal conditions and lower electric consumption resulting in lower running costs. 

It is important to note that optimizing installation setup plays an equally significant role towards achieving desirable performance rates with different types of heating systems including ground/air source ones.

Importance Of COP For Air Source Heat Pumps

Air source heat pumps are efficient and cost-effective solutions for heating homes or businesses in temperate climates.

  • COP ratio helps determine how efficiently a given model transfers heat compared to its energy usage.
  • A higher COP value means that more useful heat is being obtained from every unit of electrical power used than with a lower COP rate.
  • translating into significant energy savings year round if operating at optimal temperatures and climate conditions.
  • In general, an air source electric heat pump should have a seasonal performance factor (SPF) above 10 when operating in cold climates like Canada or Alaska.
  • However an ideal field-measured average annualized HSPF should exceed 13 for maximum efficiency.

Ideal COP Range For Optimal Efficiency Of Air Source Heat Pump

Air source heat pumps (ASHPs) are becoming increasingly popular for home heating and cooling due to their superior energy efficiency. 

COP number tells us how effective a heat pump or air conditioner is at transferring heat, compared to the same amount of electricity input needed to operate it.

The ideal range for optimal efficiency in ASHPs typically lies between 2-4 with many models delivering average COPs of 3.2 –3.6 depending on external temperature ranges and climate conditions present during installation and operation times.

Additionally, through proper sizing and installation of the heat pump system plus regular maintenance activities like changing filters regularly can help keep an ideal 4+ COP value running throughout its entirety without compromising performance over time.

Factors Affecting Air Source Heat Pump COP

The COP of an air source heat pump (ASHP) can be significantly affected by a variety of external factors, such as temperature and climate, the type of refrigerant used, size and quality of the unit, proper installation and insulation, and regular maintenance.

External Temperature Of Air Source Heat Pump

This is an incredibly important factor for air source heat pumps (ASHPs). For an ASHP to operate efficiently, it needs external temperatures that are above freezing. 

The ideal temperature range for optimal efficiency with an ASHP is 20-30°F at night and 35-45°F during daytime hours. 

Extremely cold temperatures can cause a decrease in the Coefficient of Performance (COP) of the system and pose challenges for cooling or heating appliances.

Climate Considerations For Air Source Heat Pump

When compared to areas with mild climates which may maintain consistent temperatures above 60°F throughout winter months, these colder regions require additional planning to ensure peak performance from the air source heat pump system.

Type Of Refrigerant Used Of Air Source Heat Pump

The type of refrigerant used in air source heat pumps is one of the key factors that can affect its efficiency. 

Refrigerants are substances with certain properties, like boiling point and thermal conductivity, which allow them to be used to transfer temperature from one place to another.

Different refrigerants have different efficiencies when it comes to energy conversion, so it’s important to choose the right type when installing a heat pump. 

Generally speaking, R-410A has higher heating capacity than other common types such as R-22 and R-427A and acts as a more efficient pressure regulator.

Too much or too little refrigerant charge can reduce performance considerably – leading up 10% reduction on COP (coefficient of performance) – indicating an up 15% reduction in cooling capacity and 3% in heating capacity for all size compressors running at optimum load conditions.

Size And Quality Of Air Source Heat Pump

The size and quality of an air source heat pump can have a significant impact on its coefficient of performance (COP). 

A properly sized system with high-quality components is essential for optimal efficiency.

To ensure good performance, the unit must be able to produce enough heating energy to match the desired temperature within the home or space it is running in. As such, oversized or undersized systems will not provide as efficient COP values.

Proper Installation And Insulation Of Air Source Heat Pump

Proper installation and insulation of an air source heat pump (ASHP) are essential for optimal performance. 

Improperly installing an ASHP often leads to a decrease in its Coefficient Of Performance (COP). A high COP is necessary for efficient operation and maximum energy savings.

When correctly installed according to manufacturer guidelines with properly sized vents and ducts as well as adequate attic or crawlspace insulation, heat pumps have been known to achieve COP values close to 5.

Other Factors Of Air Source Heat Pump

Various factors contribute to varying levels of achieved COP including external temperatures and climate types but also type of refrigerant itself used within. 

  • Size & quality differences amongst different brands.
  • Insulation standards provided
  • Up scale components installed.

Benefits Of A Higher COP

A higher COP means improved energy efficiency, cost savings, reduced carbon footprint and greater environmental friendliness.

Energy Efficiency A higher COP (Coefficient of Performance) is directly associated with increased efficiency and potential savings.A higher COP means lower consumption in terms of both cost and natural resources because more useful heat is gained from less electrical energy inserted into the system in order to achieve optimal performance.Investing in a higher COP model can provide numerous benefits compared to conventional systems utilizing electric resistance or oil heating solutions. 
Cost SavingsAir source heat pumps are an environmentally friendly choice for home and office heating, offering significant cost savings while also giving off fewer emissions than traditional gas-powered systems.
Environmental FriendlinessAdditionally, ASHPs do not require burning gases indoors, eliminating any potential risks related to exposure to carbon monoxide fumes or other types of pollutants.
Reduced Carbon FootprintAir source heat pumps with a higher COP can be an important part of the effort to reduce carbon emissions and strive toward Net Zero. Air source heat pumps with a high COP can help reduce carbon dioxide and other greenhouse gas emissions by up to 80%, compared with traditional fuel sources. This renewable heating can replace existing boilers that are powered by fossil fuels, which release large amounts of dangerous pollutants into our atmosphere 
Economic BenefitThe electrification of space heating and water heating using air-source or ground-source heat pump technology can bring about significant economic and emissions reduction potential.

How To Improve COP Of Air Source Heat Pump?

By implementing the right measures and selecting high efficiency models, homeowners can significantly improve their air source heat pump’s COP and save on energy costs in the long run.

Upgrade To High Efficiency Models

Energy efficiency is key to making air source heat pumps (ASHP) an effective and affordable choice for households and businesses. 

Upgrading to high efficiency models helps lower energy costs while reaping the many environmental rewards of renewable heating systems.

Modern ASHP designs now incorporate advanced components such as thermostatic expansion valves (TEV), which can improve their performance. With TEVs, heat capacities are further enhanced and electricity consumption reduced by more than 50%.

Proper Sizing And Installation Of Air Source Heat Pump

Proper sizing and installation is a critical factor in achieving an optimal coefficient of performance (COP) for air source heat pumps. 

When the size of the system is not accurately determined, or if it’s poorly installed, it can significantly reduce the efficiency of the unit.

Inaccurate sizing can lead to inadequate heating capacity for extreme cold weather conditions as well as lack of proper cooling when needed during warmer days; both resulting in higher electricity usage.

It is important that contractors follow best practices such as calculating loads based on recommended energy efficient building standards and installing appropriate insulation material where applicable to optimize efficiency.

Heat pump manufacturers also provide their own sizing requirements for different climate conditions which need to be taken into consideration when selecting an appropriate model and ensuring its effective operation within various temperature ranges.

Using Supplementary Heating Sources

The use of supplementary heating sources in tandem with air source heat pumps (ASHP) can greatly improve the COP or coefficient of performance and energy efficiency.

Supplementary heating sources work through a hybrid configuration, where they provide supplemental warmth when demand is greater than what an ASHP can supply alone.

These electric add-on sources have proved highly efficient at boosting comfort levels while still providing significant utility bill savings compared to traditional HVAC solutions – up to 70%.

Furthermore, proper sizing and installation are essential factors for matching the capacity increase provided by these systems with those needed in specific spaces throughout the home or commercial building.

Implementing Geothermal Heat Exchange

Geothermal heat exchange is a technology that takes advantage of the energy stored in the ground to improve the efficiency of air source heat pumps. 

Geothermal systems make use of this by linking one side of a conventional air-water heat pump system to an underground network through which fluid circulates before being pumped back into the building.

Other advantages include, 

  • lower running costs due to higher efficiency when compared with conventional HVAC systems.
  • lower emissions as geoexchange offers access to net zero carbon solutions like solar and other renewable sources via a dedicated grid connection. 
  • and scalability allowing easy adaptation between different size buildings as often encountered in deep retrofit projects.

Practical installation considerations include availability of groundwater for hybrid designs – such as 

Aquifer Thermal Energy Storage (ATES)

It balances between both local geology & hydrology limitations versus designing new boreholes capable enough to meet desired operational life expectancy for possible aquifers present beneath sites.

Regular Maintenance And Cleaning Of Air Source Heat Pumps

Regular maintenance and cleaning are fundamental for air source heat pumps as it helps to optimize their performance and ensure the most efficient operation.

Proper Upkeep Of ComponentsAir source heat pump Coefficient of Performance (COP) is highly dependent on proper upkeep.It includes monthly filter checks on the indoor unit, monitoring airflow (which should exceed 350 cfm per ton), inspecting all fluids including refrigerant levels, and cleaning the evaporator coil to facilitate sufficient airflow.
Regular Inspection Of SystemSimple inspections can identify any worn components that need replacement before they affect heating capacity or decrease efficiency ratings of equipment during peak demand periods in cold climates or areas with high humidity.
Service VisitsRegular maintenance also ensures compliance with manufacturer instructions related to annual service visits like checking operational stability, lubricating parts etc.
Cleaning DebrisIt’s important to keep up with regular maintenance tasks such as cleaning debris periodically that can interfere with fan speed adjustments or restrict airflow through coils.

Challenges In Achieving High COP

These include seasonal variations, extreme temperatures and limited efficiency in some models.

Seasonal Variations

Seasonal variations can affect the COP of air source heat pumps due to changes in external temperature and climate. 

During colder periods, increasing the set-back temperature or harvesting energy from alternative sources such as geothermal energy may help increase overall COP performance.

When talking about air source heat pumps, it is important to understand seasonal COP variations

The colder the environment outside the house, the harder it becomes for a heat pump to maintain an efficient operation as energy input increases in order to produce useful heat output.

Heat pump efficiency is impacted by external temperatures and climate conditions, meaning that a lower or higher COP can be observed depending on the season.

Extreme Temperatures

Extreme temperatures can have significant effects on the coefficient of performance (COP) of an air source heat pump.  

In addition, extreme temperatures might also significantly affect air source heat pumps’ ability to generate enough thermal energy with a high COP, leading eventually to over-consumption of electrical power and costly heating bills.

Limited Efficiency In Some Models

Some models have limited efficiency in achieving high coefficient of performance (COP).

The COP indicates the efficiency with which a given ASHP operates and is calculated by taking the ratio between its generated useful heat energy divided by electrical input or total energy it consumes.

Affordable Air Source Heat Pumps With High COP

High COP air source heat pumps are becoming increasingly popular in energy-efficient homes due to their efficiency and cost savings potential.

The efficient technology included in these systems allows them to meet the demand with less energy, translating into significant cost reductions on monthly bills. 

AFSHP Air-Source Heat Pump

AFSHP (Air-Source Heat Pump) can provide your home’s heating needs for years at a fraction of what traditional heating sources may have charged you previously.

The affordability of high COP air source heat pumps relies upon several factors such as initial costs, installation fees, and ongoing maintenance costs. 

Greener Homes Air Source Heat Pumps

Where customers get the option to select higher COP pumps with good efficiency rates when compared with most common units.

What Is A Good COP Value For An Air Source Heat Pump In Cold Climates?

A Coefficient of Performance (COP) of 2.0 or higher is a good value for an air source heat pump in cold climates. 

A COP that is too low indicates poor performance and insufficient energy efficiency for operating in colder climatic conditions, while one that is excessively high may reflect inadequate capacity to meet heating needs.

Energy Saving Tips With A COP

Maximizing the COP (Coefficient of Performance) of an air source heat pump is essential to increasing its energy efficiency.

A higher COP leads to lower electricity consumption and thus reduced running costs.

One tip that professionals should consider when maximizing their air source heat pump’s efficiency with a COP above 4 is to upgrade to high-efficiency models capable of handling extreme temperatures better than traditional heating systems.

To further improve energy savings from these advanced heating units it’s important to ensure proper sizing and installation due to differences in weight when selecting your unit size according ton building sizes or environment settings.

Additionally regular maintenance through cleaning filters are key elements that contribute towards improving ASHP performance substantially especially before cold seasons approach for optimal performance results.


What is a COP for an air source heat pump?

COP stands for coefficient of performance and it is the ratio of useful energy output over energy input in a heat pump system. 

  • In a typical system, this indicates how much usable energy can be produced by the air source heat pump in relation to the amount of electricity being used to power it. 
  • The higher the COP, the more efficient a unit will be and reduce overall operational expenses.

How does an air source heat pump work?

Air source heat pumps use refrigerant coils and fans to transfer thermal energy between environments essentially taking existing warm or cool air from one place, compressing it via refrigerant gas, moving that compressed heating/cooling agent through different stages until reaching its intended target location.

What are some common uses for an air source heat pump?

An Air Source Heat Pump can offer reliable direct heating/cooling all year round while simultaneously cutting down on operating costs which makes them suitable alternatives .

Not only residential purposes but also commercial ones too, given ample space requirements come installed, think large buildings such as office blocks’,cinemas’, ‘gyms’,’ schools’ etc. 

Are there any benefits associated with installing an air source heat pump ? 

The primary benefit when using this type of system is its comparatively low installation cost especially when contrasted against ground, water well tiles, geo(thermal) sources.

Reduced usage fees resulting from improved efficiency ratings so even users typically spend around 1000 of dollars fitting  these up if they opted going DIY route. 


Air source heat pumps are an energy-efficient, cost-effective, and renewable alternative to traditional heating systems. Understanding Coefficient of Performance (COP), the ratio of heat produced per energy consumed, is important to ensure you get the best out of your air source heat pump. 

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