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What product warranties should be specified in a proposed lighting solution?

Before going ahead with an installation, make sure that you understand suppliers’ warranty policies to avoid those that are not appropriate for your project. Policies should guarantee that if sold products fail to operate in accordance with warranty, a supplier will provide a free replacement of a failed product, within the validity period of the policy and subject to the warranty terms and conditions. You should provide your supplier with details of factors which may impact the lifespan of the lighting for your particular use, e.g. switching and dimming patterns, the ambient temperature, humidity in the installation, cleaning and so on.

The following enquiries should be made:

  • Does the warranty cover a minimum 5 years for a product and 12 months for the installation?
  • Does improper installation affect or potentially void the warranty?
  • How reliable is the business offering the warranty? What is the age of the business and its financial stability?
  • Does the warranty specify a maximum number of burn hours per annum?
  • Does the warranty provide a clear definition of “failure” of the light source?
  • Does the warranty policy indicate the lifespan of a lighting unit?
  • Does the warranty cover the maintenance cost?
  • Does the warranty cover labour costs?
  • Does the warranty clarify who bears responsibility and cost of replacing failed products?
  • What lighting components does the warranty cover?

Consider the below example to evaluate whether an offered warranty policy is appropriate for your lighting system.

You purchase an LED lamp with 5-year warranty and of an L70 lumen maintenance rating of 30,000 hours. It is also stated in your warranty policy that the burning period must not exceed 6,000 hours per year.

The lighting operates 15 hours per day, 365 days per year. Your annual burn hours are thus 5,475, resulting in 27,375 burn hours for 5 years. Hence, your warranty policy expires a few months before your lighting system will reach the L70 rated life.

If your LED lamp fails within the first 5 years of operation, it could be then assumed* that it was defective or faulty rather than over-burned. You should be then entitled to a replacement, repair or other compensations agreed in the warranty policy.

*Subject to other terms and conditions agreed with your supplier.

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