Installing your own heat pump: what can you do yourself?

Yes, you can carry out part of a heat pump installation yourself. With a monoblock air-to-water heat pump, many preparatory, mechanical and hydraulic tasks are suitable for DIY installation. This requires professional planning, suitable components, compliance with manufacturer instructions and a clear distinction between DIY tasks and work reserved for qualified contractors.

At DiY-Heizung, you receive more than a standard heat pump package. Your system is designed for your building, with calculations, hydraulic planning, coordinated components, installation documents and personal support. The installation is checked before commissioning. Final on-site commissioning is carried out by our qualified technicians or a suitable specialist service, according to the agreed scope.

Updated October 4, 2026

The short answer

Installing a heat pump yourself does not mean designing the device yourself or opening a refrigerant circuit; you install a mass-produced system according to project-specific planning.

Typical DIY tasks include the foundation, positioning equipment, wall penetrations, heating pipework, hydraulic components and pipe insulation. Electrical connections, grid connections and any necessary refrigerant work are reserved for qualified or certified professionals.

You do not have to undertake every suitable task yourself. Your DIY work can be combined with services from local heating and electrical contractors.

What is a DIY heat pump kit?

A DIY heat pump kit is more than an indoor and outdoor unit. It combines a factory-built heat pump with technical planning, the required system components and support throughout installation.

It is important to distinguish DIY installation from a homemade heat pump:

• DIY installation: you install a factory-built heat pump in accordance with the plans and manufacturer instructions.
• Homemade system: the heat pump itself is designed or assembled from components outside a standard manufactured system.
• DiY-Heizung: we supply a system designed for your project using factory-built components.

Installing a standard manufactured heat pump yourself does not automatically make it an excluded homemade system.

Which heat pump is suitable for self-assembly?

A monoblock air-to-water heat pump is suitable for many DIY projects. The refrigerant circuit is sealed within the outdoor unit at the factory. The connections between outdoor and indoor equipment predominantly carry water. This allows someone with appropriate practical skills to carry out more of the hydraulic installation without opening the refrigerant circuit.

In the case of split heat pumps, refrigerant lines connect the indoor and outdoor units and work on this circuit may only be carried out by suitably qualified or certified professionals.

Ground-source and groundwater heat pumps often require permits, boreholes, wells or extensive excavation. Their suitability for DIY work must be assessed for each project.

Planning and frost protection are also essential for monoblock systems. Outdoor water pipes, drain-down arrangements, insulation and the response to power failures must suit the overall system design.

What work can you do yourself?

With appropriate practical skills, you can carry out tasks marked “yes” after planning and instruction.

Clarification of grid connection and electrical conditions(German)

Why is planning more important than the assembly set?

The heat pump must suit the building, heat emitters and hydraulic system. Selecting it by floor area or consumption alone is not enough.

Before ordering, we assess the heat load, heat emitters, flow temperature, hot water demand, flow rates, pipe sizes, storage tanks and control strategy. Installation location, noise protection, pipe routes, defrost water and electrical requirements also matter.

An oversized heat pump may cycle frequently. An undersized system may lack sufficient capacity on very cold days. Room-by-room calculations also show which heat emitters are adequate and where changes would help.

Hydraulic balancing(German)

Can a heat pump work in an older home?

Yes, a heat pump can work efficiently in many existing buildings. Underfloor heating is not a mandatory requirement.

What matters is the flow temperature required to keep every room warm on cold days. Lower required temperatures generally allow the heat pump to operate more efficiently.

Existing radiators should therefore not be replaced indiscriminately. It is often sufficient to replace a few undersized radiators, improve hydraulic balancing and set the heating curve correctly. Room-by-room heat load and heat emitter calculations identify where changes are actually needed.

This is how a project with DiY-Heizung runs

After the initial assessment, we discuss installation locations, pipe routes, hot water and your DIY tasks. Technical planning, a project-specific quote and delivery of the specified components follow. Installation is supported by hydraulic diagrams, drawings, instructions and advice. The installation is checked before commissioning is arranged.

Our separate process page explains the complete journey, from gathering information to support after commissioning.

This is how your heat pump self-build kit works

What does the complete kit include?

The scope of supply follows the plans. Depending on the project, it can include the heat pump, indoor and outdoor units, storage tanks, pumps, valves, safety components, pipework, controls and components for multiple heating circuits. Hydraulic diagrams, calculations, installation documents, support, system checks and organised commissioning are also provided according to the agreed package.

A home with underfloor heating may need a different hydraulic design from a building with radiators or several heating circuits. A fixed standard package does not adequately account for these differences.

How much does a DIY heat pump installation cost?

The total cost includes more than the equipment. It may include the heat pump, storage tanks, hydraulic components, installation materials, planning, electrical work, foundations, pipework, commissioning and any changes to radiators or other heat emitters.

Your saving depends on the work you can undertake and the complexity of the project. A fixed saving cannot be guaranteed. Foundations, pipework, hydraulic installation and insulation in particular can reduce paid installation work.

After initial planning, you will receive a project-specific offer that shows you which components and services are included and which tasks you can take on yourself.

Can a DIY installation receive a grant?

Grants may also be available for DIY projects. Your own labour is not eligible, but directly related material costs may qualify under the applicable rules. Correct installation and expenditure must be properly confirmed.

A factory-built heat pump installed by its owner is not automatically an excluded homemade system. Clarify the application, contract and permitted start date before beginning work. Current grant rates and deadlines are provided on our grants page.

Check current heat pump grants →

What we often find in practice

Problems usually occur where planning and installation meet. Common mistakes include selecting equipment by floor area alone, ordering materials before the hydraulic design is complete, failing to assess existing radiators, planning pipe routes too late, inadequate protection of outdoor pipes and booking an electrician too late. Commissioning should only be scheduled once the system check is complete.

DiY-Heizung therefore selects components based on the calculations and system design. Changes during installation must be agreed and documented.

Advantages and limits of self-assembly

DIY installation can reduce installation costs and help you understand your system thoroughly. Project-specific documents, coordinated components, support and checks guide you through the work.

It also requires practical skills and time. Manufacturer instructions must be followed, and electrical and refrigerant work remain the responsibility of qualified professionals. Installation errors or unapproved changes can affect efficiency, safety and warranty rights.

Frequently asked questions

Can I install a heat pump completely on my own?

No. Depending on the project, many mechanical and hydraulic tasks are suitable for DIY work. Electrical connections, grid connections, necessary refrigerant work and certain inspection and commissioning steps remain the responsibility of qualified professionals.

Do I need a floor heating system?

No. Existing radiators may also be suitable. Their output at the planned flow temperature and the room-by-room heat load are what matter.

Do I automatically lose the guarantee through my own contribution?

Not automatically. The specific warranty conditions, compliance with the plans and manufacturer instructions, and proper documentation and commissioning are decisive. A manufacturer warranty is separate from any warranty offered by DiY-Heizung.

What happens to questions during assembly?

Depending on your service package, DiY-Heizung provides support by WhatsApp, telephone or video call. Before commissioning, the installation is checked against the project documents.

Install it yourself, with professional planning

You can carry out part of a heat pump installation yourself when DIY tasks and specialist work are clearly separated. Heat load, suitable heat emitters, correct hydraulic design and fully coordinated components are essential.

DiY-Heizung combines the potential savings of DIY installation with technical planning, clear documents, personal support, a system check and organised commissioning.

Want to see how other homeowners completed their projects? Read our customer stories.

Experiences with DIY heat pump installations

“Great help, including quick answers on WhatsApp.”

Stefan Timme from Krefeld(German)

“Good value for money.”

Arne from Schiffdorf(German)

“…it more than paid off.”

Vigh Balazs from Stuttgart(German)