Posted by Doug Root on 26th Mar 2020

How often should you change UV light bulbs in HVAC air purification units

Ultraviolet(UV) light is a proven technology that has been around for over 100 years. The first UV lights were used to treat tuberculosis. Since then they have been used extensively to kill mold, fungus, bacteria and viruses. UV light can be used to treat air, water and surfaces. UV germicidal lights have a clear quartz glass sleeve and produce a blueish light when turned on. This light is extremely harmful to humans and should never be viewed without proper eye and skin cover.

germicidal uv light

The most commonly use UV light for HVAC & Air Purifying units are referred to as UV-C or Germicidal light. UV-C light has a very short wavelength of 253.7 nanometers. At this wavelength the UV light is extremely harmful to our eyes and skin so should never be used in an un-shielded environment. This short-wave ultraviolet light interrupts DNA base pairing which in turn causes the formation of pyrimidine dimers which lead to death of bacteria, viruses and protzoa . In air cleaning applications, ozone production is an unwanted by product. Ozone can be dangerous when released and not collected. Ozone free germicidal lamps are the product of choice for HVAC air purification units. Many manufacturers like Osram produce these lamps. Osram does a great job of labeling their products that are ozone free. The sku will have an identifier "OF" so you know you are using a lamp that is not producing harmful ozone. 

Germicidal UV 2 Pin lamps

These systems are installed in homes, medical facilities, research labs and businesses. It is imperative that UV-C lamps are replaced on a regular basis. The germicidal UV-C lamps have a useful average life of 5,000 to 9,000 hours. Useful life means that during this time the lamp is operating at an optimal output level for neutralizing mold, fungus, bacteria and viruses. Inherently, fluorescent technologies like UV germicidal lights depreciate in output over time. These lamps should be replaced before the EOL(End of Life), as the amount of UV radiation emitted decreases over time despite the lamp still providing light. The lamps may be giving off light, however after useful life has been reached the lamps will be emitting a decreased UV radiation. 

4 Pin 2G11 Base UV Germicidal Lamp

Usage of the HVAC system ultimately determines how often you should replace the UV lights in your air purification units. We recommend changing your UV germicidal light at least every 12 months to maintain a clean, healthy environment. Lamp life is generally 6 to 12 months for most brands. You can expect to spend $10 to $60 per year for new lamps depending on whether you have a 1 lamp or 2 lamp system in place.

If you need help identifying your lamp or have questions regarding germicidal UV-C lamps. Please reach out, we are here to help 1-888-988-2852