Yes, germicidal lights absolutely require maintenance to remain effective. Here’s what you need to know:

Bulb Replacement is Critical:
- Loss of Germicidal Effectiveness: The most crucial maintenance item is replacing the UV-C lamp (bulb). Unlike regular light bulbs that simply burn out, germicidal UV-C lamps lose their germicidal effectiveness over time, even if they still appear to be glowing. The special phosphors inside the bulb that produce the UV-C wavelength degrade.
- Typical Lifespan: Most manufacturers recommend replacing UV-C lamps every 9,000 hours of operation, which equates to approximately 12 months of continuous use. For coil-sanitizing lights that run 24/7, this means an annual replacement is usually necessary. Some high-quality lamps might last up to two years (around 17,000 hours) with only a minimal (e.g., 20%) decrease in output. Always check the manufacturer’s specific recommendations for your model.
- Why it Matters: If you don’t replace the bulb, you’re essentially running a regular light bulb with no real germ-killing power, wasting energy and not getting the intended benefits for your indoor air quality.
Cleaning the Lamp:
- Dust and Debris Buildup: Over time, dust, dirt, and other airborne particles can accumulate on the surface of the UV-C lamp. This buildup acts as a shield, blocking the UV-C light from reaching the air or surfaces it’s meant to disinfect.
- Cleaning Frequency: It’s recommended to wipe down the lamp periodically, often every 6 months, using a clean, dry cotton cloth or paper towel.
- Handling Precautions: Always wear gloves when handling the lamp, as oils from your skin can leave residues that also diminish UV output and may cause the lamp to heat unevenly. Never look directly at the lit UV-C bulb, as it can cause eye and skin damage. Turn off the power to the unit before cleaning or replacing the bulb.
Ballast Check (Less Frequent):
- The ballast is the component that powers the UV-C lamp. While ballasts generally have a longer lifespan than the bulbs (often 5 years or more), they can fail. A professional HVAC technician will typically check the ballast during routine HVAC maintenance.

Why is regular maintenance so important?

Ensuring Effectiveness: Without proper maintenance, your germicidal light simply won’t be doing its job of killing pathogens and preventing mold growth.
Protecting Your Investment: Regular maintenance ensures you’re getting the full benefit from your investment in indoor air quality technology.
Optimizing HVAC Performance: For coil-sanitizing lights, consistent operation with a fully effective bulb helps prevent biofilm buildup, which in turn maintains HVAC efficiency and can reduce energy costs and the need for coil cleaning.