As a full service HVAC provider, National Gas and Oil Conversion LLC has been assisting the local Rockville Centre community consistently and effectively throughout the years. An air conditioner requires regular maintenance for the unit to function effectively and efficiently throughout its years of service. Our team of air conditioning, heating, and ventilation experts can install new systems, repair existing ones, and provide preventative maintenance. It is our goal to ensure that you are 100% satisfied with all the work we do.