Refrigeration - Revenue Quality

Hi Folks! Curious whether anyone in the community has experience transacting with Refrigeration companies - specifically those focused on Commercial Ice-makers. Our team is looking for anyone with relevant industry experience (as either investor/operator) trading in these companies. We are trying to confirm our understanding of key diligence items - and that we aren't missing anything major (re: Revenue Quality - Maintenance vs. Break/Fix, Labor Trends, Safety, Customers etc.).