A combination of ground loop and indoor heat pump

The Ground Loop
The loop is made of high-density polyethylene pipe, extraordinary durable but which allows the heat to pass through efficiently, not retarding the exchange of heat between the ground and the fluid in the loop. The fluid conductor in the closed circuit loop is a combination of water and an environmentally safe anti-freeze solution.

Most loops for ground source systems are installed either horizontally or vertically in the ground, or are submersed in water in a pond or lake. Each type of loop configuration has its own unique advantages.

Horizontal Ground Closed Loops
This configuration is usually the most cost effective when adequate space is available. Trenches are dug 1-2 metres in depth into which the loop is laid. The loop is installed in a coiled shape to ensure maximum and optimum coverage. The trenches are then backfilled making the system totally unobtrusive.

Vertical Ground Closed Loops
This type of loop configuration is ideal for homes where space is insufficient to permit horizontal installations or where the ground is rocky close to the surface, or for installations where minimum disruption to the landscape is required. Vertical holes are drilled into the ground 50 to 120 metres deep. Each hole is installed with a single loop of pipe with a U-bend at the bottom, then backfilled. Each vertical pipe is then connected to a horizontal pipe, which is also concealed underground. The horizontal pipe then carries fluid in a closed system to and from the heat pump.

Pond Closed Loops
If a home is near water, such as a pond or lake, this type of loop design may be the most economical. The loop is run underground to the water, then submerged in long sections underwater, and works in the same way as the ground loops. It is recommended that a pond loop only be used if the water level never drops below 2 metres at its lowest level to ensure sufficent heat transfer capability.