Lochinvar PLT30003 Flame Sensor And Gasket For FB Series Sizes 1500-3500 New Lochinvar Part Number 100165923 Used On Lochinvar Models: FB 1500, FB 2000, FB 2500, FB 3000, FB 3500, FB1500, FB2000, FBL 3500, FBL 2500, FBN 3000, FBN 2500, FBN 5000, FBL 3000, FBL 4000, FBN 3500, FBN 4000, FBL 5000, FB2500, FB3000, FB3500, FBL3500, FBL2500, FBN3000, FBN2500, FBN5000, FBL3000, FBL4000, FBN3500, FBN4000, FBL5000