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Grant air source heat pumps


Air source heat pumps use basic thermodynamic principles to convert latent heat contained within the air we breathe into heat energy that can be used to provide heating and hot water. This ‘ambient heat’ is replenished by the sun making our heat pumps both effective and environmentally friendly.

How they work
There are two basic types of air source heat pump – ‘air to air’ and ‘air to water’. Grant Aerona heat pumps use an air to water system which utilises heat energy captured from the air in ‘wet’heating system radiators or underfloor heating. The process uses the same vapour/compression cycle that extracts heat in a domestic fridge. A refrigerant with a low boiling point is exposed to external air temperatures in an evaporator. The liquid boils off to a gas and absorbs the latent heat energy of the air. This gas is then compressed increasing the heat content in the refrigerant, before passing through a heat exchanger where it condenses back to a liquid state while transferring the heat to the water of the heating system. The liquid refrigerant is then re-circulated through the evaporator and the cycle is repeated.

Fit for the future
Grant has two ranges of single phase heat pumps with outputs up to 21.5kW – the Aerona and the Aerona HE.  With the recent fluctuations in price and supply of fossil fuels, Grant air source heat pumps offer both an environmentally and economically sustainable alternative.  Home heating in the UK accounts for approximately 30% of CO2 emissions and the heat source used by Grant Aerona heat pumps is entirely renewable which helps reduce the amount of harmful greenhouse gases being released into the atmosphere and, in so doing, lowers the carbon footprint of the household.

Heat pump cylinders
Grant has a range of stainless steel cylinders specifically matched to the Aerona heat pumps, which incorporate a larger primary coil for quicker heat transference. The cylinders are available in seven indirect single coil versions, ranging from 125-400 litres and five indirect twin coil versions ranging from 170-400 litres. Grant Heat Pump cylinders feature compression fittings which are conveniently located to make installation quicker and easier. For further information, click here.

Domestic Hot Water (DHW) Boost kit
Whilst it is possible to raise the DHW to 60°C with an Aerona heat pump, it can be more efficient to set the hot water temperature between 45°C and 50°C and utilise Grant’s Domestic Hot Water Boost kit to take the cylinder up to the desired higher temperature. This unit comprises an enclosure with 20A rated contactor, an override switch and relay, which works with the immersion element fitted in all Grant cylinders.

Sealed system kits
Sealed system kits are available to suit all heat pump models. The kits come in either a 12ltr or 18ltr size for standard systems and a 50ltr size for use with the ThermaWave thermal store. For further information, see the Grant product price list.


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