School hybrid heat pump system proves the benefit of addition
Hawthorn Primary School in Cantley, Doncaster has installed a hybrid heating system, replacing an ageing system with a lower-carbon solution designed to improve comfort and efficiency across the site’s multiple buildings.
The school is set on a campus comprising several buildings of varying ages and construction types, creating challenges for consistent temperature control and system performance. The existing heating infrastructure, which consisted of two ageing open-flued boilers alongside undersized pipework, had struggled to meet demand efficiently, resulting in high gas consumption and unreliable comfort levels, particularly during colder months.
To address these issues, Keighley-based installer Service 2 (HVAC) was appointed to design and install a new system capable of delivering dependable year-round performance while reducing carbon emissions. The resulting specification was a 450kW hybrid system from Ideal Commercial Heating combining two 50kW ECOMOD 290HT air source heat pumps with three wall-mounted Evomax 2 150kW commercial condensing boilers operating in cascade.
The heat pumps are located externally adjacent to the plant room and feed buffer vessels, while the Evomax 2 boilers are installed internally on a frame-and-header kit with pre-formed insulation kits and a plate heat exchanger to ensure separation between the primary and secondary circuits.
This configuration allows the heat pumps to satisfy the majority of the school’s heating and hot water demand throughout milder seasons, Ideal said, with the boilers automatically providing support during periods of lower external temperatures. Fan coil units optimised for lower temperature operation were installed in selected areas to further enhance system performance.
In addition, a building management system (BMS) intelligently selects the most appropriate heat source depending on weather conditions and load requirements.
As the project involved an existing education facility rather than a new-build, the system was designed to be integrated with much of the original distribution infrastructure, the company adds. To provide separation between the primary and secondary circuits, preventing potential dirty system water from circulating through the new equipment, a plate heat exchanger was also installed. Other works included the construction of a dedicated concrete base and secure fencing for the external heat pump units to meet health and safety requirements.
Chris Snowden, Technical Operations Manager at Service 2 said:
The benefit of using the ECOMOD heat pumps is we can create up to 75°C hot water, which means you don’t have to change radiators. We can still run on the original system.”
Service 2 also used Ideal Commercial Heating’s free commissioning service on both the heat pumps and boilers, which the manufacturer notes ensures correct configuration and automatically applies a five-year warranty.
