The Challenge
Balancing low-carbon heating with the high-temperature demands of healthcare facilities creates significant specification challenges. For this NHS hub in Doncaster, the primary requirement was maintaining strict Domestic Hot Water (DHW) storage temperatures to ensure compliance and reliable peak-load delivery.
The Solution
To meet these demands, we installed two Strebel NTi45 Air Source Heat Pumps in a dedicated compound, running on R290 natural refrigerant. These units are specifically designed for high-temperature output, making them ideal for critical healthcare environments. The NTi45 units feed a Strebel S-LC-I1000 calorifier located inside the plant room.
Safety and Commissioning
Because R290 is a low-lying gas, Strebel’s dedicated engineering team provided full on-site commissioning to ensure the installation complied with all local and national regulations. The commissioning process included calibration checks, mechanical systems, and critical safety elements.
The NTi45 units incorporate multiple fail-safes, including gas sniffers at the base and within the inverter board. If gas is detected, the system shuts down and activates a dedicated extract fan, removing any risk to the plant room and keeping the site safe.
The Result
The project was successfully delivered, installed, and commissioned, delivering 90 kW of high-temperature heat. The R290 heat pumps generate 80°C hot water leaving the units, allowing the system to comfortably achieve and maintain a 65°C DHW storage temperature within the 1,000L calorifier.
By pairing high-efficiency equipment with factory-backed commissioning, the NHS hub now benefits from an uncompromised, low-carbon hot water system built for real-world hydraulic realities.
