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Air source heat pump installations are increasing day by day. Future heat pump installation objectives will also boost the need for skilled installers. Engineers installing heat pumps must be educated to guarantee proper installation. They must also be licensed to deliver years of dependable, low-carbon heating. As with any heating system, engineers must follow the Installation and Servicing Manual when installing an air-source heat pump. Planning, site surveys, and property appraisals start the process. Heating and hot water are needed. Every house needs something different. Installers must work closely with their clients to ensure they specify and install a heat pump system that fulfils their needs.
Every air-source heat pump installation is different, but certain factors are universal. In this comprehension, we will understand the air-source heat pump schematic.
Introduction to Air Source Heat Pump
Air-source heat pumps employ a refrigeration circuit operated by an electrical compressor to convey heat from a supply to a demand. For household structures, this source may be ambient air or heat from the earth, which can be captured to offer heating (or cooling) without using fossil fuels.
All heat pumps use the same principles but vary in components, operation, and size. Due to better fabric efficiency, modern apartments and smaller dwellings may require a modest air source heat pump. In contrast, more substantial older buildings may need bigger air-source heat pumps or ground-source heat pumps to produce the essential heat supply.
What are the Types of Heat Pumps Systems?
There are two main types of ASHP: air-to-air and air-to-water source heat pumps. The ASHP system is classified into monobloc and split variation. Discover the specifics of all in the below chart.
Air Source Heat Pump | Ground Source Heat Pump | Monobloc and Split System |
ASHPs use a fan to push atmospheric air through a heat exchanger (evaporator) to recover heat. Most heat pump components are self-contained. Thus, they are easy to install. Air temperature varies both throughout the day and across different seasons. This means ASHP’s performance is changeable, reducing when the air temperature is lower, especially in winter. | GSHPs move water through pipes. That is placed deep to recover heat. As the underground lines need to be hidden, trenching/drilling boreholes can make installation more difficult. Depending on the area’s bedrock. The ground keeps a much more steady warmth throughout the year than air. This means a GSHP can usually achieve better rates, especially in winter when the air is cooler above ground. | Monobloc heat pumps are tightly sealed units that produce hot water distributed straight from an external unit. Split-system heat pumps include internal and outdoor units linked by refrigerant pipes, which produce hot water (from the internal unit). Many newer heat pumps are monobloc, which eases their installation as they do not require handling any part of the refrigerant system. |
List of Parts Used in a Domestic ASHP System
ASHP system works through several components. Here is the list of their category and details.
Component | Category | Description |
General valves | Connection | Various control and operating functions |
Heat pump pipework | Connection | Contains working fluid within the heat pump |
Communication interface | Electrical | Enables external sources to interact with the heat pump |
Inverter | Electrical | Controls the speed of the compressor |
Casing | Housing and frame | Protects internal elements |
Mounting brackets | Housing and frame | To mount the equipment/unit on a flat surface |
Casing insulation | Insulation | Reduces heat loss and noise levels |
Pressure sensor | Production | Monitors pressure for safety and efficient operation |
Temperature sensor | Production | Monitors temperature for safety and efficient operation |
Filter | Production | Prevents contaminants/damage in airflow and water flow |
Control system | Production | Enables analysing and smart control of the system |
Fan (including motor) | Production | Increases airflow, improving heat pump efficiency |
Flow switch | Production | A sensor that monitors the flow rate and pressure of a working fluid |
Compressor | Refrigerant | Circulates refrigerant around the heat pump |
Reversing valve | Refrigerant | Reverses the gas flow to allow heating and cooling modes |
Expansion valve | Refrigerant | Reduces the pressure and temperature of refrigerant |
Accumulator | Refrigerant | Prevents liquid refrigerant passing through the compressor |
Refrigerant buffer | Refrigerant | Stores excess refrigerant when the system is not at total capacity |
Evaporator | Refrigerant | Recovers heat from a heat source and deposits it into the refrigeration circuit |
Condenser | Refrigerant | Deposits heat from the refrigeration circuit to the end user |
Expansion vessel/device | Refrigerant | Maintains the desired pressure in the system |
Glycol | Refrigerant | Prevents inline water freezing |
Refrigerant | Refrigerant | A working fluid that is effective at transporting heat |
Air Source Heat Pump Installation Process
As stated above, every system is different. Installing an air source heat pump will change significantly between new builds and retrofits. Still, any heat pump installation should always contain these key steps:
- Pre-installation Planning includes an entire site study and correct property room-by-room heat loss estimate. It also includes discussing the customer’s needs and selecting the goods needed for the installation based on the heating system’s design.
- Installation- Every heat pump should be installed according to the manufacturer’s installation and servicing directions. A typical heat pump installation may take longer than a boiler replacement. Because it requires more startup steps and system checks. All new or replacement sources chosen, such as radiators and underground heating, will need to be sized and appropriately put. It is used with a heat pump to achieve the required heat output. All system pipes must be sized, fitted, and lagged adequately. The heat pump, heating, and hot water system must be thoroughly set up and commissioned.
- Post-Installation- Customer handover is essential to any heat pump operation. Once the heat pump has been successfully installed and commissioned. The installation engineer should perform an in-depth handover with the end-user. Thus, they are familiar with and sure about how their new heat pump heating system works.
Tools Required to Install an Air Source Heat Pump
Extras and key components are needed for the system when installing an air source heat pump. The process involves the following steps:
- Pipework Insulation- Insulate all internal and outdoor system pipes with a proper insulation grade. Free ASHP Grant UK offers a through-wall insulation kit, which includes heavy-duty insulation to fit through the property’s wall and around the rubber tubes tied to Aerona³ heat pumps. If all system equipment is not adequately protected, this will negatively impact the heating system’s performance.
- Electrical Wiring- The placement of a heat pump involves electrical wire. So, the fitting worker needs to be appropriately trained and able to finish these parts of the installation work. A qualified electrician may be required at different steps of the building process.
- Specialist Access Equipment- Additional equipment may be required based on the manufacturer’s maximum installation height if a heat pump is wall-mounted. Equipment such as platforms and proper steps may be necessary to enable safe working. Any Grant Aerona³ R32 heat pump wall mounting is possible if the top is no higher than two metres above the ground.
Selecting the Optimal Air Source Heat Pump Size
Choosing the ideal heat pump size is essential to ensure proper and efficient operation of the heating and hot water system.
Installation Best Practices
Below, we have listed a few of the most excellent options for outstanding heat pump installation techniques. However, for the best installation services, please enroll in Free ASHP Grant UK’s online: applyforgovernmentgrants.co.uk
Start with Good Design
We have stated it before, but every heat pump installation should start with the planning, design, and specification of the heating system. The entire system plan must be known before any components are implemented. A heat pump installation involves many technical factors. Taking the time to design the system will make the installation simple. It also helps ensure users have a properly built and efficient heating system.
Location and Positioning
Ensure the heat pump is firmly fixed on top of proper anti-vibration mounts. And that all of the necessary clearances are reached around the unit. It is also essential to place the heat pump thermostat in line with the advice given in the installation and service instructions. And that all safety rules have been met.
Water Circuit Pipework and Appliances
This is a big update and should involve checking or finishing the following. The water lines should be made tight and safe. A good in-line filter should be correctly placed. The pressure gauge should be correctly fitted on the sealed system pipes or expansion tank manifold. Connection lines should be adequately supported. The extension tank should be designed sufficiently to manage the system quantity. A volumiser tank should be added unless a buffer, thermal store, or combination buffer/cylinder is connected to the heat pump system.
The whole heating system should be appropriately cleaned out. And it is particularly crucial when placing a heat pump on a present system. After cleaning, an appropriate heat fluid should fill the system. Any Legionella protection installed on the system should be set up based on a risk assessment of the customer’s sensitivity. All system piping should be adequately shielded. A flow control should be placed on the heat pump’s return pipe to ensure the minimum flow rate is reached. And it is kept through the heat pump at all times.
Electrical Connections
All electrical work must be performed by a competent person and fixed as outlined in the installation and service instructions. A separate power source with a correctly sized breaker must be used. The final power source must be from a protected, locked breaker outside the house.
Check the Refrigerant
Grant Aerona³ R32 air source heat pumps are all air-to-water and have a monobloc design. The refrigerant is pre-charged into the unit during the making process. Any work needed on the refrigerant circuit must only be carried out by a competent person with the appropriate F-gas qualification.
Ensure Clear Drainage
Heat pumps can produce several gallons of water daily, depending on the air level and activity. On the bottom of the Aerona³ R32 heat pump, there is a condensation opening that allows water to drain from the heat pump. The installation or service engineer must ensure that provision is made to collect and dispose of this liquid properly. This condensate mustn’t be allowed to run onto walks or streets, as it will turn to ice during the winter.
Get A Free Air Source Heat Pump Grants In the UK
The UK government also offers free ASHP grants through the ECO4 Scheme. The scheme encourages low-income homes to install low-carbon heating systems like air-source heat pumps. These grants cover the cost of ASHP systems.
Installing an air source heat pump will vary slightly based on whether it’s an upgrade or a new build. However, there are three main steps in the whole process:
- Pre-Installation – local study and judging fit
- Installation – Installation of indoor and outdoor units and joining them
- Post Installation – finishing and care
Conclusion
Air-source heat pumps use free energy from the surrounding air to provide warmth. These systems work with smart components. Thus, they are ideal for renovation and allow for flexible placement.
Even though an air source heat pump’s main job is heating, its reverse operation allows it also to cool. This provides a pleasant living temperature in all rooms, not only in the cooler months of the year but also in the hot months. We hope our comprehensive guide provides complete details about the ASHP’s schematic. This is the future of sustainable heating, so the government of the UK also focuses on providing free ASHP grants to needy homes to promote cleaner energy. People can lower their energy bills and enjoy a free heating system.
Frequently Asked Questions
Larger and well-insulated pipes (22mm or more) are needed to handle lower flow temperatures and ensure efficient heat distribution for heat pumps. Upgrades to existing pipework may be required to support the system’s temperature needs.
The amount of pipework needed for an air source heat pump depends on the size of your home and the layout of your heating system.
The five main components of a heat pump are:
- Compressor
- Condenser
- Expansion Valve
- Evaporator
- Refrigerant
