ACV Gasket sight glass 55412027

This gasket, ACV part number 55412027, is a sealing component for the sight glass on ACV CA heating equipment. Its compact dimensions are 47x47x21 mm. It is designed to be placed between the sight glass and the housing, ensuring a tight seal and preventing leakage of the working medium. This part is intended for replacement when the sight glass gasket is being serviced on ACV CA units.

Sight glass gaskets of this type are selected by exact dimensions—inner and outer diameter and thickness—and by the material appropriate for the application. Common gasket materials include fibre, graphite, or silicone; the choice depends on the medium (water, steam, or flue gas) and the maximum operating temperature and pressure. Before ordering, measure the old gasket and confirm the part number matches the original assembly. When installing, ensure the sealing surfaces are clean and free of old gasket residue, and torque the retaining fasteners evenly to the manufacturer's specification—overtightening can crack the glass.

Over time, sight glass gaskets of this kind can harden, compress, or degrade from temperature cycling. The first sign of failure is typically a leak at the sight glass joint—dampness, drips, or staining around the viewing window. In more severe cases, the equipment may lose system pressure due to the failed seal. During service disassembly, inspect the gasket for cracks, flat spots, or loss of elasticity.