Rock Hill, SC Noise from Specific Sources: HVAC & Mechanical Noise (2026)

The core residential noise standard in Rock Hill, § 20-162(18), caps noise 'within 300 feet of any residentially occupied structure' at 60 decibels measured at the lot line, but the same subsection lists specific exemptions, and item (i) removes HVAC equipment outright: 'sound which was generated by an HVAC unit' is exempt from that decibel cap. That puts a condenser unit, heat pump or rooftop commercial HVAC system in the same exempted category as sound from a permitted stadium event or an authorized emergency vehicle, meaning a neighbor cannot bring a decibel-based complaint against ordinary HVAC operation no matter how it measures at the property line.

The broader prohibited-noise section, § 20-161, technically still applies to any noise that 'disturbs, injures or endangers the comfort, repose, health, peace or safety of others,' so a badly maintained or defective unit that becomes an unreasonable disturbance is not necessarily untouchable, but the city has no numeric HVAC standard to enforce against. only if it stays under 75 dB(A) measured from the nearest residential property, a numeric ceiling HVAC equipment does not have to meet at all.