Lennox Healthy Climate X4575 UV 2002 Ultraviolet Air Purifier

Air purifier, installs in supply duct. 2 years old. 1 year old bulbs. Fairly easy installation.
Manual here: Healthy Climate® germicidal light - Lennox https://www.lennox.com/dA/361a09347f/Lennox_0UV_IOM.pdf