“This has been an extensive upgrade programme, implemented in phases across the campus, which will deliver significant energy and carbon savings for the University,” explained the University’s Project Engineer. In replacing the existing steam boilers it was expected to see a considerable reduction in maintenance costs.

The boiler replacement programme began in 2010, following an in-depth assessment of the boiler market. Hoval was selected as the principal boiler supplier on the basis of product quality & reliability, energy efficiency and lifecycle costings. In addition to boilers, Hoval has supplied a wide range of expansion vessels and pressurisation units.

In the campus’ main boiler house, for example, a number of options were considered as replacements for the existing steam boilers. The most economic and practical option was identified as using four Hoval SR-plus steel shell boilersto feed the low-temperature hot water circuits. Four FS Micron pressurisation units and one PressVal unit with integrated expansion vessel were also installed in this plant room. This part of the upgrade programme alone is predicted to reduce the University’s carbon emissions by over 4,500 tonnes per annum.

Each plant room was evaluated to determine the most efficient solution. Where low return water temperatures were available Hoval UltraGas condensing boilers have been installed to take advantage of the opportunity for improved efficiency from condensing. In the plant room at the Castle Leazes hall of residence, for instance, the existing boilers have been replaced by 6 x 1MW UltraGas boilers. In other plant rooms a combination of UltraGas and SR-plus boilers is being used to provide optimum efficiency.

In total, Hoval has so far supplied 11 UltraGas boilers, nine SR-plus boilers, four expansion vessels of various sizes,11 FS Micron pressurisation units and three PressVal pressurisation units with integrated expansion vessels.

“The programme is now nearing completion and we have been very pleased with the support we have received from Hoval throughout the project,” the University’s Project Engineer added.