The doctors at St John's Villa surgery in London needed a new heating and cooling system for their refurbished practice. They wanted to create the perfect indoor climate where they could treat patients in a comfortable and draught-free environment.
Unsurprisingly, many of their patients were unwell, some actively infectious and others at risk of picking up an infection. They therefore needed to reduce the risk of transmission of airborne infection. In addition, there could be no hot surfaces as some patients would be frail nd at risk of injury.

The architect recommended two Hi-Velocity small duct systems with three-part air purification (HEPS) modules added-on. This provided:

• Ultraviolet lamps to kill viruses and bacteria.
• A high-level filter to reduce allergy causing airborne particles.
• Honeycomb photo-catalytic oxidation to reduce chemicals, volatile organic compounds and smells.

The Hi-Velocity system is designed to deliver heating and cooling in a way that ensures heat is delivered evenly and comfortably.

The patients will not feel a draught, even when the system is in comfort cooling, says the system's supplier. Two Hi-Velocity systems were installed with 14kW reverse cycle electric heat pumps.

Both systems were fitted with an air purifier. Seven-day timer controls allow the systems to be programmed.

The air purifiers help control the spread of airborne infection; there are no hot surfaces during heating
and no cold draughts during cooling. Positioning the air outlets in the ceiling, wall and floors maximised the space in each room.

www.hvsystems.co.uk