What's the difference between equipment breakdown and commercial property?

Standard commercial property insurance covers property damage from external perils: fire, theft, storms, vandalism, falling objects. It explicitly excludes mechanical and electrical breakdown of equipment, because those are considered different risks with different underwriting. Equipment breakdown insurance (sometimes called 'boiler and machinery' historically) covers the internal failures that commercial property excludes: boilers exploding, HVAC compressors burning out, electrical arcing, motor burnout, transformer failure, refrigeration system failure leading to spoilage. The two policies complement each other. A restaurant that has commercial property but no equipment breakdown is uncovered if the walk-in cooler compressor fails and the inventory spoils. Most modern commercial accounts carry both; equipment breakdown is often added as an endorsement to business owners policy or commercial property for $200 to $1,500 annually.