Pentair Piping Assembly Upper | Triton C TR100C / TR140C Sand Filter | 156355 Pool Liners The Pentair Shaft Seal (U109-372SS)

The Pentair Shaft Seal (U109-372SS) is the OEM replacement shaft seal for Pentair pool and spa pumps

sand bypasses the filter bed and enters the pool return lines — a clear indicator that one or more laterals need replacement

Worn or seized bearings cause uneven wheel speed

the cleaner loses suction-driven propulsion — resulting in erratic movement

Pentair Piping Assembly Upper | Triton C TR100C / TR140C Sand Filter | 156355 Pool Liners The Pentair Shaft Seal (U109-372SS)The Pentair Piping Assembly Upper (156355) is the OEM replacement piping assembly for the Triton C TR100C and TR140C sand filters, routing filtered water from the filter tank to the multiport valve outlet. What It Does The upper pipe assembly forms the internal water pathway between the filter's distribution system and the valve connection at the top of the tank. When this assembly cracks, warps, or develops leaks, water bypasses proper filtration and