Canopy Housing, a community charity, is dedicated to eco-renovating Victorian terraces in the area, helping reduce fuel poverty and providing affordable heating solutions for residents.
Project Overview
Canopy Housing’s mission involves retrofitting empty homes to create sustainable, low-carbon housing. Many of the homes they renovate face issues like damp and cold, common in older properties. To improve efficiency and reduce costs, we selected the Ariston NIMBUS Pocket air source heat pump, which met the property’s heating requirements while also being compact enough to fit in the limited space available.
Installation and Design
The installation required thoughtful planning to adhere to space constraints and noise regulations. We worked with the compact NIMBUS Pocket unit, measuring only 1016mm wide, which fit within the available space while meeting MCS 020 Sound Assessment requirements. The sound level needed to stay below 42dBA at neighbouring properties, so we sited the unit near the kitchen door steps, ensuring it complied with local development rules.
To deliver consistent heating, we designed the system for low operating temperatures, setting the flow temperature for the radiators between 41–45°C and the domestic hot water between 50–55°C. We also installed new radiators that matched these specifications to keep the property warm and efficient.
The NIMBUS heat pump uses R32 refrigerant, which allowed us to work within the tight clearances of the property. Unlike other refrigerants that need larger safety zones, R32 was ideal for this setup, maintaining both safety and efficiency.
Efficiency and Environmental Impact
With a Seasonal Coefficient of Performance (SCOP) of 4.08, the NIMBUS unit efficiently delivers 4.08kWh of heat for every 1kWh of electricity consumed. This level of efficiency is essential for Canopy Housing’s goal of reducing running costs for residents, especially those at risk of fuel poverty.
By switching from the previous gas boiler to this heat pump, we anticipate a reduction in CO₂ emissions from 3.7 tonnes to 0.9 tonnes per year, saving nearly 3 tonnes of carbon annually. This savings is expected to increase as more renewable sources are added to the UK electricity grid.
This installation was recently featured on BBC Morning Live as part of a segment on the importance of energy-efficient retrofits to meet the UK’s 2050 Net Zero goals. It is available to watch on BBC iPlayer until 28.08.2025. Watch it here (starts at 43 mins 50 seconds in).