Large Retrofit Domestic Ground Source Heat Pump Installation

The Background

Large Retrofit Domestic Ground Source Heat Pump Installation

A rural renovated barn house in the heart of Cheshire countryside now has a green and sustainable form of heating.

Moblake Farm is occupied by the Grieves family and has provided their livelihood for multiple generations. The 300m2 property has had numerous extensions added to it over the years, with the main house construction being cavity filled walls and standard double-glazed wooden windows.

Due to being off the gas grid an oil boiler had been used to heat the home but this was very expensive to run and coming to its end. Thus, the Grieves family wanted to shop around for a more environmentally friendly and cost-effective solution.


Specialist installer JM Renewable Solutions (JMRS) Ltd were asked to provide a solution and recommended a Large Retrofit Domestic Ground Source Heat Pump Installation as the best option for Moblake Farm.

Mr. Grieves contacted JMRS for advice on their heating options. They were attracted to the renewable heating system for environmental reasons as well as the potential financial benefits from running cost savings and the Renewable Heat Incentive programme,” said Ben Musgrave of JMRS.

There was plenty of adjacent land to install the ground collector loops and the heat pump would fit nicely in the assigned plant room within the house. This was a complex project due to the space that needed heating, and the fact that the central heating system in some areas would upgrading. We engineered a heat pump solution and the installation of fan assisted radiators ensured efficient heat distribution around the house. The hot water had previously been heated by an oil-fired Aga that had no temperature controls. Now, the hot water is provided by the heat pumps in a much more efficient way. The Grieves will receive regular RHI payments and also save considerable amounts on their heating bill now that they are no longer relying on oil.

The excavation consisted of 5 trenches, each trench contains a 205m ground loop, dug 1m deep and 1 m wide. The pipe then feeds into the assigned plant room inside the property. Due to the high heat loss of the property (18KW), JMRS designed and installed a MasterTherm AQ inverter driven 7-22Kw unit, accompanied by a 300L hot water cylinder and 100L buffer tank.


Most retro-fit installations pose unique challenges but JMRS drew on their considerable expertise in this field to ensure that it was a smooth and seamless installation. The house is now maintained at comfortable temperatures across all rooms. This is an impressive example of how old properties can benefit from renewable energy systems. Mr Grieves has saved approx. £840 per year on his annual heating bill (old system-oil) and he will be receiving £4500 per annum from RHI payments; thus demonstrating how old properties can benefit from the latest technology.