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case study

Gas, plumbing & drainage

A drone photograph of a crane from above

The existing heating system was over 25 years old and required a lifecycle replacement programme. We conducted an energy-efficient assessment involving a systematic survey to analyse the current energy usage, identify areas of improvement, and recommend the most suitable heating boilers to enhance energy efficiency. Data collection including reviewing maintenance strategies, energy bills and consumption patterns, occupancy levels and trends, energy modelling and cost analysis were captured during our assessment before presenting a proposal to our client for their subsequent approval.

This project was to replace 3no Hoval Cosmo 290 boilers located within a rooftop plant room. The first challenge was to get the 3no 600+kg boilers down off the roof, which we outsourced to our specialist supply chain partners. Devon Lifters attended with their 40t mobile crane and made a runway to get the boilers out of the plantroom and then lifted off onto a trailer to be recycled in line with our ISO 14001 accreditation.

With the old boilers removed, we could start with the installation of 6no Vaillant ecoTec 120 kW boilers mounted on a frame, with a new 720 kW plate heat exchanger which hydraulically separates the new boilers from the old system.

A new flue system was also designed and installed utilising the existing flue to drop a new liner from the terminal to the rooftop plant room.

A new efficient Pressure Set System was also installed where pressure is actively controlled to ensure the primary circuit is pressurised at all times.

All works were completed during a 6 week Summer Holiday programme of works that there was no disruption to the college education programme and extracurricular building use.

An image of newly fitted gas boilers at Exeter college
An image of a Sherwoods gas engineer fitting some pipework
An image of some newly fitted gas boilers at Exeter college
Two Sherwoods engineers fitting pipework
A crane being used to lift new boilers in place
Old boilers being removed
Fitting the new boiler fronts