NuTone C905 Door Chime Transformer 16V 10VA Low Voltage AC

The NuTone C905 door chime transformer is a 16-volt, 10-VA device that converts a standard 120 V AC mains supply to a 16 V AC secondary suitable for most NuTone door chimes, making it a common replacement for aging or failed transformers. Designed specifically for single-chime installations, this open-frame transformer delivers 16 VAC at up to 10 VA to reliably power the chime mechanism while staying within typical load ratings. It includes a built-in thermal cut-off switch that shuts the unit down if temperatures rise excessively, helping protect both the transformer and the chime wiring, and it offers flexible mounting options with lock-mount or wall-mount configurations for a neat installation behind the chime box. Often sold in multipacks (for example, packs of six) to support multi-door setups, the C905 is a standard choice when a NuTone transformer is required for door chime systems.