Heat pumps are a viable technology that efficiently provides warmth and heated water. While the UK is still reliant on fossil fuels, heat pump adoption is a growing trend. Currently just 1% of homes use heat pumps as a primary source of heating and hot water. For every heat pump sold, there are 15 gas boilers purchased.
But, as of 2024 UK heat pump sales were recorded at 98,345, up from 62,906 from 2023. Between 2025 and 2030 the UK heat pump market is expected to expand by 11.10% CAGR. So, how can a heat pump benefit the property of a business owner or homeowner? Rinnai can demonstrate the benefits of real-life heat pump installations through case studies that display the advantages of heat pump adoption in a commercial application.
A BREEAM EXCELLENT SCIENCE PARK
The location is a three-story Welsh science park with a BREEAM excellent facility providing offices, laboratories, and workshops for up to 700 people. It functions as a central hub for start ups, research teams and established technology focused organisations.
Wales’ first dedicated science park selected a custom Rinnai R290 High Temperature ASHP system with full Modbus BMS integration to support its low carbon heating and hot water strategy. The installation includes 10 27kW R290 heat pumps, sourced from Rinnai’s 21–27kW R290 range.
Each unit delivers a SCoP of 3.21 at a 65°C flow temperature, supported by a custom designed 3000 litre buffer vessel engineered for the site’s needs. The system is capable of producing high temperature output up to 75°C, and all units were supplied with anti corrosion protection to ensure durability in the park’s coastal environment.
The science park selected Rinnai after assessing the company’s R290 high temperature heat pump range, technical capability, and in-house design experience. Rinnai delivered a complete, site-specific solution including:
• 10 × 27 kW R290 ASHP units, each treated with anti corrosion coating for coastal protection.
• A custom built 3000-litre buffer vessel engineered for mechanical compatibility
• Full Modbus BMS integration for streamlined control
• Optimised rooftop configuration to minimise height and distribute system weight.
Rinnai’s R290 technology is low-GWP, quiet operation, enables water temperatures up to 75°C, and ensures compliance with European F Gas phase down regulations. For tailored system selection the client also accessed
Rinnai’s design support tools. The science park now benefits from a future proof, low carbon heating and hot water system that reduces operational impact while maintaining high performance. Key outcomes included:
• Meaningful carbon reduction through R290 low GWP refrigerant
• High temperature output suitable for laboratories, offices and workshops
• Greater energy efficiency, supporting long term cost control
• Resilient system performance with anti-corrosion protection
• Seamless BMS integration for optimal operation.
The Rinnai range also includes scalable larger systems for future expansion, such as the 40–410kW R290 commercial series. The Welsh science park now operates a reliable, efficient, and low carbon heating and hot water system aligned with long-term sustainability goals.
COMMERCIAL OFFICES IN LONDON
Another example of Rinnai’s heat pumps providing operational efficiency to a commercial site is located at a landmark office development in central London that required a high-performance domestic hot water solution capable of meeting peak occupier demand while fitting within a tightly constrained plantroom envelope.
A leading building services engineering consultancy worked with Rinnai’s low GWP commercial heat pump technology to design a DHW system comprising two 40kW R290 air source heat pumps, complete with plate heat exchangers and DHW storage.
The resulting solution successfully meets a daily hot water demand of approximately 1,600 litres, achieves a rapid recovery time of around 85 minutes at -7°C ambient temperature, and delivers a future ready, low GWP refrigerant strategy with integrated safety and control measures embedded into the system design.
The client is a leading independent, global multi-disciplinary consultancy delivering innovative and sustainable engineering solutions for complex commercial developments. The practice is particularly experienced in the delivery of Grade A office buildings, where plant space optimisation, resilience, and low carbon performance are critical to both landlord and occupier requirements.
The office building required a domestic hot water system capable of supporting a daily demand of approximately 1,600 litres, with a maximum recovery period of 120 minutes, to ensure reliable service during peak occupancy.
Rinnai UK worked with the project team to develop a high temperature R290 air source heat pump solution, specifically configured for commercial DHW production within a restricted plant environment. The proposed system used two 40kW R290 inverter monoblock air source heat pumps, supported by high temperature plate heat exchangers, inline buffer vessels, and DHW pre feed storage, ensuring both hydraulic stability and rapid recovery performance.
Rinnai UK’s early design engagement helped provide confidence from concept stage through to proposed installation, supporting both technical compliance and broader sustainability objectives.
www.rinnai-uk.co.uk/products