A dusty smell at first startup each season is often normal, but it should fade quickly

https://winterhavenactroubleshooting420.scriblorax.com/posts/the-real-cost-of-repeated-ac-breakdowns-repair-bills-vs-replacement-price

A dusty smell at first startup each season is often normal, but it should fade quickly. If it lingers, replace the filter and have the unit cleaned professionally.