PHPI looks at how one Oxfordshire homeowner transformed their ‘hard to heat’ home with a renewable heating system.
Consumer interest in heat pump technology was already high prior to the rise in fuel prices. The growing interest in heat pumps has also been boosted by recent changes to Part L of the Building Regulations and the Government’s desire to move away from traditional fossil fuel boilers on the UK’s journey towards Net Zero.
As renewables become more appealing, it is worth looking at how technology such as heat pumps and Solar PV can be suitable for both new build properties and older properties.
Challenges
In December 2021, the owners of a four-bedroom, detached Oxfordshire property decided to upgrade its central heating system. At the time the home was heated by an oil boiler and the owners, who care deeply about the environment, wanted to switch to a low carbon alternative. They contacted one of Grant UK’s G1 Installers, Busy Energy Ltd, for advice who identified several challenges in making the switch.
“The property was your typical ‘hard to heat’ home”, explained Adrian Liddell, the company’s Managing Director. “The property had smaller pipework and radiators to suit a higher temperature fossil fuelled system which meant it was not possible to simply disconnect the boiler and re-connect a heat pump with the upgraded cylinder.”
“Also, the property is in a very rural, quiet location and the outside of the property is tastefully finished so the aesthetics had to match the property’s character as well as being designed to provide the correct comfort levels whilst remaining affordable to operate.”
Busy Energy recommended the Aerona³ 17kW R32 air source heat pump, which has the largest output available in Grant’s heat pump range. With a twin-fan unit which achieves excellent efficiencies, it is compact in design and has been awarded the Quiet Mark.
“The property where the Aerona³ heat pump is fitted has a large downstairs area then upstairs is similar to a large dormer where in effect most of the rooms are in the roof, so the correct insulation levels had to be installed ahead of the heat pump installation. A heat pump may not have been the obvious answer for this home but we were able to design a system that meant that an air source heat pump could be successfully installed to meet the household’s heating demand.”
Solar
A Grant QR 300ltr pre-plumbed cylinder was also installed, which incorporates a large stainless internal coil, allowing for efficient heat transfer within the cylinder; it also has a high level of insulation to ensure low standing heat losses, and so makes for a good combination with the heat pump.
“We also recommended solar PV as part of this installation,” continued Adrian. “It was installed with an 8.2kW battery store system which diverts power to the property or the heating as required and stores power for evening use. 900m of underfloor heating pipework was also fitted alongside new radiators throughout the upstairs of the property – this was all designed to MIS3005 standards.”
The installation of the new heating system was completed in February 2022 and the heat pump is currently outperforming an oil boiler which is fitted in a neighbouring property, also owned by the client.
