A UV lamp is a scheduled replacement, not a failure item. Its UV-C output falls steadily through life while the lamp continues to light normally, so a reactor with visibly working lamps can be well below its dosing duty. Replace on elapsed operating hours against the measured intensity trend, not on the lamp going out, and handle the new lamp by its ends only. Wedeco Ecoray lamps are low-pressure high-output amalgam lamps matched as a pair to their ballast; using an unmatched lamp or ballast forfeits the efficiency, warm-up and dimming behaviour the pairing exists to provide. Wedeco was founded in Herford, Germany in 1976 and is now a Xylem brand.