Beckett 3666U Oil Burner Splined NutBeckett 3666U Oil Burner Splined Nut is designed for reliable replacement on SF SM residential oil burners. This essential oil burner part ensures a secure, tight connection within Beckett burner assemblies, helping maintain optimal performance and long service life. Crafted to fit the 3666U configuration, it provides a precise spline engagement for consistent operation in home heating systems. Ideal for preventive maintenance or replacement when

Applications: Residential and Commercial

oil 5–135 PSI AC / 5–100 PSI DC)

Use it as part of your ASCO valve parts inventory to maintain steady flow

The kit is backed by genuine AO Smith engineering

It is compatible with typical Belimo valve accessories and supports reliable control in demanding environments

factory pre-charged air at 50 PSIG

offering straightforward installation

Helps maintain accurate temperature control

it ensures a secure fit and consistent actuation

It handles air

and promotes safer operation in everyday use

Applications: Ideal for hot water service