Can Ground Source Heat Pumps Provide Hot Water?

Can Ground Source Heat Pumps Provide Hot Water? Yes, ground source heat pumps (GSHPs) can provide both domestic hot water (DHW) for showers, baths and hot water taps, as well as heating a property. They take heat from the ground via pipework buried in the ground and then increase that temperature using a refrigeration circuit. This heat is then transferred to a suitable hot water cylinder where it is stored until required.

How a ground source heat pump heats water

A ground source heat pump uses a heat transfer fluid pumped through pipes or boreholes in the ground to collect naturally occurring heat from the earth.

The compressor in a heat pump increases the temperature of the refrigerant, which then passes heat to the heating and domestic hot water systems in the property.

The hot water is heated by passing heated primary water through a heat exchanger coil in an indirect hot water cylinder.

Do you need a special hot water cylinder with a ground source heat pump?

Generally yes. A hot water cylinder compatible with heat pumps and having a heat exchanger coil of the right size is normally needed for a ground source heat pump.

The heat pump has lower primary flow temperatures than conventional boilers and therefore needs a larger surface area coil so that it can transfer heat efficiently into the stored domestic hot water.

The cylinder must be sized to the heat pump’s heating capacity, operating temperatures and the required hot water recovery time. Our full range is detailed here: Hot water cylinders for ground source heat pumps

Ground source heat pumps – can they reach 60 degrees C?

Yes, depending on the model and operating conditions, some ground source heat pumps are able to produce hot water at 60°C or more.

Other systems may need an electric immersion heater to achieve higher storage temperatures or to complete a Legionella control cycle.

The Coefficient of Performance (COP) of the heat pump typically decreases with increasing water temperature; hence, the hot water temperature and control strategy must be selected carefully.

Can ground source heat pumps provide domestic hot water?

Yes. Ground source heat pumps can provide domestic hot water efficiently, as the temperature of the ground is usually more stable than the temperature of the outdoor air.

Efficiency, however, relies on the desired water temperature, the design of the heat pump, the ground loop and the performance of the cylinder heat exchanger.

A well-sized ground source heat pump and appropriate hot water cylinder will give you reliable, energy-efficient domestic hot water throughout the year.