Air conditioning-based system uses heat pump technology to warm underfloor heating throughout Sidcot school.

Sidcot School in Winscombe, North Somerset was founded in 1699 to provide an education for local Quaker families and today it adheres to the founding principles of striving to enable each child to develop their talents to the full. Self-development of the pupil and high levels of pastoral care are still a high priority as is the need to find sustainable and cost-effective systems of heating and cooling.
When the Governing Body of Sidcot School were looking for a cost-effective way of keeping their pupils warm in the new Performance Arts Centre that has just opened, they were initially surprised when the building services contractors, A C Mechanical installed an air conditioning-based system that uses heat pump technology to warm underfloor heating throughout the school.
“More and more owners of commercial buildings are now realising the energy saving advantages that air conditioning can offer and it is starting to lose its image as ‘cooling-only’,” explained Lee Sherriff, who led the project at the school for A C Mechanical, which is an Accredited Installer for Mitsubishi Electric.
Six City Multi PQFY heat pump systems from Mitsubishi Electric supply water heated to 45ºC and deliver a gentle all round heat. “The PQFY underfloor heating works in tandem with an air handling unit on the roof which ventilates the building and keeps the air fresh throughout the centre,” added Lee Sherriff.
The overall system was designed by Bob Cross of Cross Consultancy to meet the school’s brief of trying to be as environmentally and sustainably active as possible.
City Multi VRF air conditioning is used to provide internal cooling in a couple of hot spots but otherwise the year-round heating and cooling is as cost-effective as possible for the school, which caters for about 350 senior pupils and around 150 in the Junior.
The PQFY water heater uses the vapour compression cycle of the air conditioning system and instead of simply discharging the heat from the refrigerant to the air as in a conventional split type air conditioner, the hot gas refrigerant pipe in the PQFY runs through the water piping in a unique tube-in-tube coaxial system that extracts the heat from the refrigerant cycle and transfers it directly to the water.
“I think we will see more and more heating systems using heat pump technology, especially as the price of oil and gas keep rising,” commented Lee Sherriff. “For Sidcot School, it just made perfect sense to install a system that they know is going to provide them with reliable and cost effective heating year on year.”