A. O. Smith Corp. has signed a definitive agreement to acquire Lebanon, Tenn.-based Lochinvar Corp. (including its United Kingdom-based subsidiary Lochinvar Ltd.) for $418 million and will not assume Lochinvar’s existing debt. The transaction is expected to close in the third quarter of this year, subject to customary closing conditions and regulatory review.

In the last year, approximately two-thirds of Lochinvar’s residential and commercial boiler revenues have come from its lines of high-efficiency, condensing products. In addition, the North American commercial boiler industry is split between hydronic heating applications and hot water applications, and A.O. Smith currently sells very few hydronic heating systems.