How are geothermal boreholes maintained?

An often-touted benefit of geothermal energy solutions is their longevity. Installed properly, the boreholes themselves can last for up to a century, but that is dependent on some regular maintenance. 

Below, we outline some of the main parts of the borehole that require maintenance attention. From the borehole itself to heat pumps and other parts of the system, these are the main things you’ll want to keep an eye on.

The borehole

The actual borehole is designed for longevity. Due to how difficult it would be to replace the internal components, the grout and loop pipework are all made from extremely durable components, and should last for 50-100 years.

In terms of maintenance, not much is necessary for the loop and borehole. It will be pressure tested and sealed during installation, and so long as everything is done properly, it won’t require any intervention during its operational lifetime.

Heat transfer liquids

To transport heat up from the depths of the borehole, liquid needs to be circulated through the ground loop. This liquid is typically some sort of mixture of water and antifreeze, to ensure that the fluid doesn’t freeze during the colder winter months. 

While this liquid will last for a while, the antifreeze can start to degrade, and might need to be replaced or topped up. It’s a good idea to test the concentration around once a year, as part of a routine service. You can also use this test to identify any other contaminants that might have made their way in.

Other components

A geothermal borehole is useless all on its own. It needs to be connected to a ground source heat pump, and it’s the heat pump and its connectors that will typically require more attention in terms of servicing.

Much like with a boiler, a quick annual check will need to be carried out to test refrigerant levels, electrical components, sensors, pressure levels, and the condition of any seals or filters. 

The importance of monitoring

All of this maintenance isn’t just done for the sake of it. It’s required in order to keep the system running at optimum efficiency. Aside from routine, planned maintenance, you can often identify potential issues thanks to monitoring systems that track key performance-related data.

Monitoring systems should be able to alert you in the event that any aspect of your system requires attention. These early indicators are worth listening to, as they can help prevent downtime and make it possible to fix issues before they deteriorate into something unnecessarily complicated and expensive to fix. 

When you have your geothermal borehole drilled and installed into a heating system, the contractor should provide you with a more detailed and specific set of maintenance instructions for your system in particular. It’s worth setting up regular maintenance visits from a geothermal borehole specialist as soon as it’s installed, so that you don’t get behind with anything. They’re expensive systems to have installed, and you want to make sure that your investment remains maximally productive and efficient for as long as possible.