P.L. Light Expert Articles: Best Practices for Cleaning Horticultural Luminaires

PL Light Systems - Lisa Jansen van Rensburg

Hybrid Lighting, LED luminaires, Light Maintenance, Maintenance | October 20, 2023

You may not realize it unless you’re regularly measuring your light levels, but it’s estimated that light output can be reduced up to 10% due to the buildup of dust and dirt on a luminaire and/or reflector.

A buildup of dirt on the luminaires can also lead to overheating and reduced performance of your lighting system. Horticultural lights that are not properly cleaned and maintained, can also result in a loss of quality in your crop, and possibly increase your crop cycle and reduce overall yield.  To maintain optimal performance for your luminaires, it’s highly recommended to include the cleaning of luminaires and/or reflectors as part of your regular cyclical maintenance routine when you are cleaning other parts of your CEA facility as well.

The summer months when the days are longer, are typically a great time for greenhouse growers to consider cleaning their grow lights, since they won’t need supplementary lighting in the greenhouse.

It’s also important to note that proper maintenance protocols are critical to ensuring the optimal performance and longevity of all greenhouse equipment. When cleaning the ceiling / walls of your grow facility, luminaires should ideally be removed from the mounting structure. If that’s not possible, the luminaires should be properly bagged to protect from the ingress of any water / cleaning agents, just like this customer did.

To clean your luminaires:

  1. As is always the case before commencing any maintenance work, be sure to turn off and lock out the branch circuit and ensure the luminaires are completely cooled.
  2. Use low pressure compressed air to remove dust and/or debris between the heat fins on the driver housing and/or LED modules.
  3. Wipe the luminaire housing down with a dry or slightly damp cloth.
  4. To remove the build up of limescale on the LED lens, lightly dampen a clean, soft cloth with a vinegar and water solution (1:100 ratio) and use it to gently wipe down the lens.
  5. Allow the luminaire to dry completely before powering on again.


To maintain the highest level of performance for your HID luminaires, it’s recommended that you also check and clean your reflectors every year as part of your regular maintenance routine.

P.L. Light Systems’ NXT family of HID luminaires are designed so that the reflectors can easily be removed for cleaning (even when the lamp is installed). So, to clean the reflectors, it’s as easy as lifting them off the luminaire(s) and washing them in the same simple vinegar and water solution (1:100 ratio) used for cleaning the lens of your LED luminaire(s). You can check out this short video for the step-by-step instructions on how to do this.

Obviously, the aluminum material of the reflectors will start to degrade over time as part of normal wear and tear in a CEA environment, so at some point, you will need to replace them if you want to maintain optimal PAR light output over the long term.

For your safety, when cleaning luminaires and/or reflectors:

  • Always maintain the correct ratio and never add other chemicals to vinegar and water solution.
  • Never clean the luminaire with corrosive cleaning agents, abrasives, or other aggressive liquids.
  • Wearing hand and eye protection is advised.
  • Any luminaire maintenance should always be performed in accordance with local and national building; electrical and/ or safety codes.