The answer to 'dimmer switch replacement schedule' is that most dimmer switches should be replaced every 8-10 years, or when they start to malfunction. Dimmer switches are mechanical devices that wear out over time with regular use. The internal components can become worn, causing the switch to flicker, hum, or stop working entirely.
It's important to replace a dimmer switch before it fails completely to avoid potential fire hazards or electrical issues. Homeowners should inspect their dimmer switches periodically and consider replacing them if they are more than 8-10 years old, even if they are still functioning properly.