Heat Pumps

A heat pump is a device that allows the transfer of heat from the air or ground into a building in a process similar to that of a fridge.

The heat pump amplifies this heat by the way of a compressor. For every 1 KW of electric input, it is possible to extract 4-5 KW of useful heat energy. This is referred to as COP (Coefficient of performance).

A good quality heat pump would have a COP of between 4 and 5.

There are 2 main types of heat pump available on the market. Ground source which is sometimes referred to as geothermal (which is incorrect), and air source.

Ground source heat pumps extracts the energy that the ground has absorbed from the sun. This is done by pumping a glycol through pipe work that is buried outside at a depth of at least 1.5 metres. This is because at this depth the ground temperature is relatively stable with a temperature of about 8-12 degrees c.

The deeper the excavation the less the ambient or seasonal temperature will affect the ground temperature and therefore the energy we can extract.

Another option for a ground source heat pump is a deep bore hole if the required space outside is unavailable. This would require getting a hole to the depth of about 150 metres drilled.

Air source heat pumps use a large fan to move air through a heat exchanger which absorbs the heat from the air. There is no major excavation works needed with air source and because of that are the preferred option especially when retro fitting.

Any heat pump installation rely on a well-insulated house and also a heating system that is designed especially for the heat source.

Heat pumps are most efficient when they are working at a low constant heat in the form of underfloor heating or fan assisted radiators with a flow temperature of between 35-40 degrees c.

Any good quality heat pump would be able to rise the temperature for hot water production to 60 degrees c.

We cannot emphasise enough the importance of the system been designed correctly to work at its most efficient. A well designed system can be as efficient as 500% with a COP of 5.

We use only quality heat pump products in conjunction with their own buffers and thermal store cylinders as recommended by most manufactures.

Manufactures use are CTC, NIBE, Samsung, Dimplex, Daikin

Shean Mechanical Contracts