The Renewable Heating Specialists

Heat Pumps can help to reduce your carbon footprint, providing clean, green heating!

We install high efficiency heat pump systems (ground source and air source) which offer a clean, reliable alternative to gas and oil heating systems. 

How does a heat pump work?

A heat pump is a device which moves heat energy from one place to another.  A domestic refrigerator is an example of a heat pump which takes heat from inside the fridge and dumps it outside (which is why the back of a fridge gets hot). A heat pump heating system works in reverse, making the inside of the house warm and the outside cold.

There are two main parts of any heat pump system:

1. A Heat Source

This can be the ambient are water, soil or rock outside the house. We install air source heat pumps and ground source heat pumps:

- Air source heat pumps

Here the heat source is the external air at ambient temperature is cooled by passing over a finned heat exchanger, thus heat is extracted into the evaporator of the heat pump.

- Ground source heat pumps

Here the collector pipe is installed in one or more trenches or boreholes. A water/anti-freeze solution is pumped around this loop of plastic pipe, extracting heat from the ground.

 

2. A Refrigeration Circuit

A heat pump works by driving the fluid around a circuit containing four elements:

- The Compressor

This compresses the refrigerant gas and when this happens the gas gets hot. This hot refrigerant gas then passes to;

- The Condenser

This is a small heat exchanger inside the heat pump. As the hot refrigerant gas passes over the heat exchanger the heat is transferred to the hot water cylinder where it is stored for later use in radiators and hot water to taps. As heat is absorbed from the refrigerant gas it condenses back into a liquid, still at high pressure. Having given up a lot of its heat, the refrigerant then passes to;

- The Expansion Valve

This is basically a small hole. Here the refrigerant gas goes from high pressure to low pressure. As the liquid refrigerant passes through the hole to the low pressure side, it evaporates and its temperature drops rapidly to minus 33°C.  This very cold refrigerant gas is then channelled to;

- The Evaporator

This is a second heat exchanger inside the heat pump. This allows the cold refrigerant gas it to absorb heat from the heat source (air or ground). As it absorbs heat, the gas warms up after which it is channelled back to the compressor and the cycle is repeated.

A heat pump can be used where there is a low temperature source of heat. The ambient temperature of the air or ground outside could be a little as 5ºC and the heat pump can still deliver heated water at 45ºC - 50ºC.

Heat pumps need to electricity to run the refrigeration circuit. The key is to ensure that the amount of electricity is small, while the energy absorbed from the air or ground is large. For example, with a 3:1 performance ratio (usually referred to as coefficient of performance or COP), 1kW of electricity used by the Heat Pump is combined with 2 kW of heat extracted from the heat source (the air or the ground) providing 3 kW of heat energy to your home.

A heat pump can therefore only be truly green if the electricity used to power it comes from renewable sources. Luckily there are now electricity providers offering 100% green electricity, which enable a heat pump to be a truly renewable heating source.

We value our independence and only install the best heat pumps on the market in the UK!

As an independent installer we install only the heat pumps we consider to be the best.   Currently we only install NIBE heat pumps.  We are fully accredited under the government’s Microgeneration Accreditation Scheme, as are these NIBE heat pumps. This means if we install your heat pump system then you are eligible for the government's Low Carbon Buildings Programme and other grants. 

NIBE Heat Pump Systems

With an Air Source Heat Pump the installation is small and discrete.  All you see from the outside of the house is a small plain box, like an air conditioning unit which can be positioned behind screening if required.

With a Ground Source Heat Pump there will need to be extensive ground works to either lay the trenches or drill the bore hole.  But once the earthworks have been completed and the pipes have been laid there is nothing visible on the outside of the house.

For more information about NIBE Ground Source Heat Pumps click here to visit the NIBE Ground Source website page. 

Or for information about NIBE Air Source Heat Pumps, click here to visit the NIBE Air Source website page.

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