S denotes sleeve on end cone for use with appliances with no combustion chamber. Approved for use with No. 2 fuel oil or lighter. We recommend 60 degree, but 80 and 45 may be used. The complete line of AERO residential and commercial oil burners is designed and engineered for the quickest, most trouble-free installation. Best of all, they're backed by one of the most extensive warranty programs in the business.
Extended warranties are available.