Ground Source Heat Pump Installation Guide
What is the step-by-step process for installing a ground source heat pump (GSHP) at your property? Of course, each project is unique but in this Ground Source Heat Pump Installation Guide we look at the common threads to our heat pump installation projects which will inform you about the typical workflow.
In this article, we will outline the typical GSHP installation process in simple terms.
Planning and preparation
Your project always needs to be planned properly. First and foremost, our experts will speak to key stakeholders about requirements, using experience and know-how to recommend the best renewable heating installation plan.
Context is critical here. How big is the property and what will its heat demands be? What is the access like? What is the current or planned heating distribution method (e.g. underfloor heating or radiators)? Is the insulation sufficient? How much space surrounds the property, and where should the ground source heat pump system be positioned? These are just a few of the important questions we need to answer before pressing ahead with a heat pump installation.
A conversation is the first port-of-call. Next, an on-site survey. Ongoing calls and meetings will establish a plan of action. This is always a bespoke approach for every project. In a nutshell, we need clarity on which system to install, how to install it, and possible obstacles on the horizon.
New-builds and renovations
This is the step-by-step process for installing a ground source heat pump at a new-build or renovated property. We will discuss retrofit GSHP projects at the end of this article.
1. Digging or drilling
The ground loop installation will happen at an early stage. This is because the builder is often on site with suitable plant and equipment, doing footings and foundations for the property construction. This is the perfect time to dig the trenches for a horizontal ground source heat pump system, or drill boreholes for a vertical ground source heat pump system.
We work installation stages into the existing project plan wherever possible, to minimise impact on timelines and to reduce costs. The digging and pipework installation stage is a good example of this approach, where we integrate with other building work at the start of construction.
2. Pipework installation
Once the trenches have been dug, we put the pipework into the ground. This is a network of pipes, the extent of which depends on the size and capacity of the system. This could be from one loop to ten, but each project is bespoke. If it is a ground loop installation (horizontal ground source heat pump), ground loops will be inserted at a depth of one metre.
These pipes are fed back to a ground source heat pump “prefabricated manifold chamber”. This chamber is embedded into the ground, and comes up to roughly floor level. We run pipework which has a bigger diameter from the manifold chamber into the property itself; directly into the specified plant room. We insulate and protect that pipework as required.
This is a similar process for horizontal GSHPs and vertical GSHPs. The only difference is that the pipework is placed into a deep borehole. This borehole requires a drilling rig to be brought onto site, as opposed to standard digging equipment. Regardless, this would also happen at an early stage for new-builds and renovations, and the pipework would arrive into the plant room through a similar framework and system structure.
3. Heat distribution
Thereafter, we tend to leave site and come back later to install and/or connect the heat distribution infrastructure. For modern properties, this is often underfloor heating on multiple levels of the property. Ground source heat pumps work best with underfloor heating, so we usually recommend this as the best solution before the build starts.
4. Heat pump system installation
The build will progress onwards in our absence, and we tend to return towards the end of the project to get the ground source heat pump system up and running. This is usually when the overall construction or renovation project is more or less complete.
Firstly, we tend to visit the site to place the equipment in the correct position in the plant room, taking into account everything else that is planned for the room. The equipment laid out is usually a ground source heat pump unit and an additional hot water cylinder. Sometimes these are combined, but most often a cylinder is separate. These are coupled together and connected to the heat distribution and domestic plumbing systems.
5. Commissioning
When it’s time to get the system up and running, we do the purging and flushing, and dose up the ground loops with antifreeze mixture. We do a similar thing with the heating system; purging, flushing, and adding inhibitors. We then wire up the system and connect the controls for underfloor heating and/or radiators.
Next, we set up the flow rates on the ground loops and heat distribution system, making sure that everything is operating as expected.
6. Handover
Once we’re happy that the system is commissioned to our high standards, we plan a handover. This often happens after we have left site. Sometimes this is a handover to the builder, and sometimes to the end-user and owner of the property. It depends on the project.
Due to the fact that ground source heat pumps are different to conventional heating systems, education and helpful handover is paramount. We often return to the property once the owner has moved in to present another handover lesson, showing how to operate the system, check its health, and other key information.
Retrofit ground source heat pump projects
Planning and preparation is no less important for retrofit projects. We will survey the property as required, and present a detailed plan of action to all key stakeholders.
In terms of the installation itself, the main difference with retrofits is the fact there is an existing system to deal with. This means we need to assess that system to see if it’s adequate, and/or to plan whether we need to upgrade anything before we install the ground source heat pump.
Furthermore, we must assess how to get pipework into the building itself. With new-builds and renovation projects, there is often a lot of building work occurring at the same time. This means that we can usually incorporate the pipework installation. Retrofits don’t usually allow for this convenience, so we need to plan around this issue. Of course, every client project is different.
The other consideration is how to decommission the existing system. If we need to upgrade elements or take out much of an old system, this needs to be done with minimum disruption. Sometimes this is as simple as draining the system and flushing it out; but this could also involve upgrading radiators to work with lower running temperatures. We might also need to upgrade pipework. This will become apparent during the initial survey.
Do you want to know more about installing a ground source heat pump? Contact us today.
