Dometic Commercial Grade rooftop air conditioners are performance-tested to overcome harsh or unusual road and weather conditions. Many standard units break down after just four hours of extreme vibration testing, while the Dometic Commercial Grade is still going strong at 30 hours and more! The Galvanized steel top plate provides lasting strength while long copper lines minimize vibration and, therefore, noise too. While being one of the toughest air conditioner around, it uses a 410A refrigerant that's kinder to the environment. Cooling Capacity: 15,000 BTU.