Installation Options

The installation of ground and water source heat pumps involves a circuit of underground pipework outside the house and the internal installation of the heat pump and tank. All ground and water source heat pumps have two parts; a circuit of underground piping outside the house and a heat pump unit inside the house.

Pipe Installation Options

The external pipework system can be installed via either an open or closed loop system.

An open system is a method of heat extraction that takes advantage of the heat retained in a body of water (this could be an underground well, a river, loch or the sea). In a closed-loop system, heat is collected from the ground by means of a continuous loop of pipe buried underground.

The primary pipe installation methods are as follows:

Closed loop installation (horizontal)

This is the most common method and is far cheaper than drilling. In this case, a series of pipe is installed horizontally into a pre-determined number of trenches and buried to a specified depth. The pipe is filled with a glycol anti-freeze mixe and is sealed prior to final system operation. The pipe loops meet at a central point (called a manhole) where they connect to a distribution manifold and are then connected back to the heat pump.

IHS also has options available for extracting heat from nearby bodies of water, such as the sea, lochs, rivers and canals.

Closed loop installation (vertical)

Thie method involves drilling a series of boreholes to a maximum depth of 100m. Sealed pipework is installed vertically into each borehole which is then backfilled. Drilling is always carried out by a specialist company. It is likely that a geological report will need to be prepared to analyse the rock type to allow for proper system calculation.

Open well installation (vertical)

This method of extracting heat involves drawing water directly from a specially drilled borehole well and conducting it to the heat exchanger where heat is extracted. The water is discharged either back to the underground water body through a separate well (preferable option) or to a substantial overground body of water. A sacrificial plate heat exchanger is almost always employed and a series of tests would need to be conducted to determine the water suitability for use with a heat pump.

Open well installation (other)