GROUND SOURCE HEAT PUMP | CONTROLS Improvement by stealth source reduced reliance on fossil fuels to give comfort control. Gas-fired boilers were installed as a backup, should the GSHP not provide the required amount of heat. The project studied the low temperature hot water circuit (LTHW), which supplies heating to the whole building, including two large air handling units that heat and ventilate the auditorium. This circuit is The benefit of system monitoring is evident at primarily pumped from the LTHW stored in the GSHP buffer vessel. Should this buffer ChichesterFestival Theatre, where a change in valve vessel fail to reach a setpoint, however, a settings produced tangible energy savings. By Jake Piner mixing valve allows the boilers to top up the LTHW circuit to a second higher setpoint. The schematic is provided opposite. f engineered correctly, a building energy management system (BEMS) will The primary focus of this study was to control indoor climate dynamically, in a cost-effective manner, ensuring the improve the use of the GSHP and reduce the comfort, safety and wellbeing of occupants. It will only be effective, however, reliance on gas-fired boilers. Understanding if the performance is maintained once the building is in use. So it is important this reliance involved monitoring the boiler that operational data is monitored. To demonstrate the benefits of ongoing blending valve. Figure 1 demonstrates how monitoring, a live building Chichester Festival Theatre was chosen as a case the blending valve is required to top up the study. Operational data was gathered, temperature changes over time were heat delivered to the LTHW circuit, opening analysed, and potential improvements to the buildings energy control 100% for considerable amounts of time. R E T S PO system were suggested and implemented. Observation showed the buffer vessel D E T P E ACC The theatre consists of a large, 1,300-seater auditorium, backstage temperature and, consequently, the l a ic Techn m area, offices and hospitality space. It underwent a refurbishment in flow temperature was dropping well Symposiu posium below the setpoint (45C) before the 2014, which included the installation of a modern BEMS that controls .org/sym www.cibse and monitors the buildings heating, cooling and ventilation plant. The valve was operating to bring it back 2019 aim was to improve its environmental performance. The installation of up. This is reinforced by the CT flow an open-source ground source heat pump (GSHP) as the primary heat temperature varying between 35C and I LTHW temperatures 05/02/18 LTHW temperatures 13/02/18 48 48 C C O O 40 32 15 32 08:00 CT flow temp 16:00 00:00 GSHP buffer 08:00 CT flow temp Blending valve 05/02/18 GSHP buffer 12:00 Auditorium air temp Blending valve 13/02/18 100 100 % % 0 08:00 22:00 0 16:00 Figure 1: LTHW temperature and blending valve operation on 05/02/18 00:00 08:00 22:00 12:00 Figure 2: LTHW temperature and blending valve operation on 13/02/18 10 May 2019 www.cibsejournal.com CIBSE May19 pp10-11 Chichester Theatre Supp.indd 10 26/04/2019 18:03