Hospital deploys Spirax Sarco heat exchanger systems
Leighton Hospital has cut its water heating costs by an estimated 10-15% per year by upgrading its hot water system to two Spirax Sarco EasiHeat steam-to-hot-water systems.
The upgrade is also expected to deliver further savings by cutting carbon emissions at the hospital, which will reduce payments under the CRC Energy Efficiency Scheme.
The installation by Leighton Hospital, a 540-bed acute hospital in Crewe, brings the total number of EasiHeats at the site to 10. Six of the existing units supply low-temperature hot water (LTHW) for the space heating system in the main hospital building, while a further two units provide a combination of LTHW and Domestic Hot Water (DHW) for some of the hospital’s outbuildings.
The latest EasiHeat systems will supply almost 90% of the DHW in the main hospital building, making the transformation from calorifiers to EasiHeat steam-to-hot-water systems in the main part of the hospital almost complete.
“Our aims in installing the latest EasiHeat systems were to achieve a more-accurate control of our outgoing water temperature, eliminate wasted energy due to storing large volumes of hot water, and reduce or eliminate scheduled maintenance works regarding annual inspections,” said Brian Colley, energy and environmental engineer at Leighton Hospital.
“We have a lot of experience with plate heat exchange systems, which meant our decision to upgrade to the EasiHeat systems was an easy one to make – we knew they would be perfect for this project.”
Spirax Sarco EasiHeat is a ready-to-install system that uses steam in a compact, plate heat exchanger to deliver water on demand at a constant, stable temperature, even with the sudden, wide load changes frequently experienced in a hospital environment. As the hot water is supplied on-demand, there is no need to store it, avoiding the associated energy losses and significantly reducing the risk of Legionella.
“Before we installed the EasiHeat systems, we had to pasteurise the water by keeping it at 80°C for an hour before we could open it up onto the circuit,” said Colley.
“Then, because it is domestic hot water, we had to cool it down before it could be used, which was a huge waste of energy. Installing the EasiHeat systems means it is no longer necessary to store hot water, which will reduce carbon emissions.”
Unlike calorifiers which are pressure vessels and must be stripped down for annual insurance inspections, EasiHeats do not need to meet this requirement, saving substantial maintenance costs.
Spirax Sarco worked closely with Leighton Hospital to make sure the switchover to the EasiHeat systems was as easy as possible.
“Due to this being the primary hot water system for 90% of our hospital, the major challenges involved ensuring constant operation of the system,” said Colley.
However, the overall scheme design, which Spirax Sarco helped to perfect, meant that very few shut-downs were needed and the hospital suffered no loss of service.”