CoilKlean UVGI / Ultraviolet Germicidal Irradiation
A common problem with building ventilation systems has been microbes growing and forming biofilms on heat exchange coils. These sticky, glue-like substances trap dust and reduce heat exchange efficiency; resulting in higher running costs. Manual cleaning damages the coils but by exposing the coils to constant UV-C light, biofilm growth is prevented.
This is where Plasma Clean’s CoilKlean UVGI comes into its own; the unit (a modular system which offers the flexibility of installation in any size. Air Handling Unit, Fan Coil or Cassette Unit) keeps the coil clean, perpetually disinfecting 99+% of viruses, bacteria, mould, spores and fungi.
Not only does this eradicate microbial growth, but it also helps to maintain optimum heat transfer across the coil surface and maximises energy efficiency.
By installing the CoilKlean UVGI, maintenance costs are reduced. There is a reduction in the transmission of airborne infection and odours throughout the building, reducing staff and customer illness. The CoilKlean UVGI can be installed into new developments and can be retrofitted into existing HVAC systems.
Introduction to UVGI • Ultraviolet Germicidal Irradiation
Ultraviolet light in the c-band range (225–302 nm) is lethal to micro-organisms and is referred to as ultraviolet germicidal irradiation (UVGI). UVGI works by cross linking nucleic acids (DNA & RNA) to prevent replication and proliferation of micro-organisms such as viruses, bacteria, spores, moulds, yeast and fungi. It is important to use the correct UV-C dosage in order to achieve high kill rates. Low intensity UV-C can be used for surface treatment as there is a long UV-C exposure time whereas high intensity UV-C is required for air treatment as the exposure time is short. Plasma Clean UVGI systems are sized to achieve up to 99% microbial kill rate for common microbes based on UV-C dosage tables in the scientific literature as well as independent testing carried out by Plasma Clean.
Plasma Clean’s germicidal range consists of the CoilKlean UVGI for surface treatment of heat exchange coils, the AirKlean UVGI unit which is a standalone air cleaner and the TechniKlean UVGI series designed to treat air in building ventilation systems.
Air Treatment using CoilKlean UVGI
UVC light prevents microbial biofilms forming on cooling coils in Air Handling Units. Biofilms are formed by the growth of mould, fungi and bacteria on the coil surfaces which are an ideal breeding ground for micro-organisms. A sticky glue-like substance produced also traps dust. By irradiating the coils with high intensity UV-C light, the coil keeps clean and maintains optimum heat transfer across the coil surface. There is also a reduced maintenance cost and an improvement in IAQ. This is a modular system which offers the flexibility of installation in any size Air Handling Unit, Fan Coil or Cassette Unit.
Sizing of Equipment – CoilKlean UVGI
To accurately specify the correct equipment to ensure optimum germicidal performance, the following information is required:
UV-C lamps are to be located 300-500mm upstream or downstream from the coil surface and sized to provide an equal distribution of UV coverage. Installing the equipment downstream has the advantage of also treating the condensate pan. Where more than one row of lamps is used, lamps are to be located a maximum distance of 900mm apart. The ballast box and control panel are to be located close to the AHU (within 2.5m of the UV-C lamps). The Coil Clean system is designed to be moisture resistant and wired using moisture resistant conduit. For surge protection purposes it is recommended to install a Class D MCB circuit breaker in the electrical supply.
For UV-C safety, the units are to be interlocked with the door and air flow to ensure the UV lamps de-energise when the AHU is opened, please enquire.
A Plasma Clean service contract is available (please enquire firstname.lastname@example.org) and in any case Plasma Clean would recommend:
Please contact us at email@example.com for quotation and pricing or if a CAD drawing is required.