Air source heat pump and solar power in four-bed Dorset home

Future-readiness

Until very recently, Maria and Kevin Burnett’s family home in Gillingham, Dorset, was still using the same gas boiler that had been installed when the 112m2 property was built in the early 1990s. Although the existing set-up was still functioning, it was definitely time for a change. “We wanted to do the right thing environmentally and prepare the house for whenever we sell it in the future,” explains Maria. “That meant things like installing an EV charger and ending our reliance on gas.”

The couple both work at Bublshop, one of Viessmann’s key merchant partners, which specialises in heat pumps, solar energy and battery storage systems. Bublshop was the first distributor in the country to stock Viessmann’s Vitocal range of heat pumps and is currently the exclusive UK dealer of its Vitovolt photovoltaic (PV) products. Maria is the company’s office manager and Kevin oversees the warehouse. 

Being immersed in the world of renewable heat and power technologies on a daily basis, they already had a sense of what was achievable, as well as the potential financial and environmental benefits and funding sources they could tap into to help finance their modernisation project. It only remained to research possible approaches in order to finalise the details. 

Says Maria, ‘We wanted to take advantage of the modern technologies that are out there. We knew we wanted a heat pump, and we knew we wanted it to be a high temperature one, too, to minimise the disruption and cost of the installation. We did our research online to make sure we both understood everything involved.” 

After looking at all the options, they chose a 13kW Viessmann Vitocal 150-A air source heat pump with integral instantaneous heating-water heater. With a maximum flow temperature of 70oC, it works with almost all of their existing radiators and there was no need to fit underfloor heating. It’s also particularly compact, requiring 60% less space than comparable models. 

“The heat pump was basically swapped out for the boiler like-for-like, with the indoor unit in the same position inside the garage and the outdoor unit just outside,” Maria recalls, “The whole process took around four to five working days. We chose to change all our existing radiators, but this was only a requirement for two of them, to the larger size, as per heat pump requirements.” The installation was carried out by renewables specialist Dorset Energy, which is a sister company to Bublshop.

Climate Protect +++

The Vitocal 150-A’s sustainability credentials were also especially appealing to the couple. It uses the environmentally responsible, natural refrigerant R290 (propane) which has a very low GWP (global warming potential) of 0.02. “We liked the idea of using a product which incorporates R290, because it’s the newer refrigerant,” Maria continues. “If you’re going to invest in putting technology like this in, you may as well make sure it’s the newest and best possible version you use.”

To power the heat pump and provide energy for charging an electric vehicle, the Burnetts also installed 14 Viessmann Vitovolt PV panels on their roof together with battery storage, further reducing energy bills.

The design flow temperature (DFT) of the heat pump system is 55oC. Thanks to Viessmann’s built-in control, there was no need for a third-party thermostat and the entire scheme is conveniently operated and monitored through Viessmann’s ViCare app.

The cost of the new system, which provides heating and hot water to the property and went live in April 2024, was offset by a £7,500 grant from the Boiler Upgrade Scheme (BUS). Running costs are anticipated to be just £19 per year, leaving Maria and Kevin looking forward to many years of zero-emission heating comfort.