Wiper holder assembly for Hanovia medium-pressure ultraviolet disinfection systems, part 320341-01. The holder is the carrier that clamps the wiper ring to the rod and keeps it square to the quartz sleeve; if it is worn or distorted the ring stops making even contact and the sleeve is left with unwiped bands. The quartz sleeve is the only optical path between the lamp and the water, so any film of scale or iron on its outer surface cuts the delivered UV dose. The wiper sweeps the sleeve on a timed cycle to keep transmission at the design figure. Supplied as a complete assembly. Reference number 22125-0916.