Aprilaire® Germicidal UV Lamp, 40 W, 9000 hr Average Life, 17-1/2 in L x 6 in W x 8-1/2 in H

• Ultraviolet germicidal lamp is designed for the lamp to be on at all times
• After 9000 hr of operation or about one-year of constant use, the effectiveness of the lamp inside the unit diminishes and needs to be replaced
• Rarely will a lamp burn out in one year of continuous use, replacement is necessary because the lamp's intensity decreases

• Instruction/Installation Manual https://assets.unilogcorp.com/267/ITEM/DOC/Aprilaire_1910_Instruction_Installation_Manual.pdf