Ferguson has acquired Western Air Systems & Controls Inc., an exclusive Trane HVAC distributor for the states of California and Nevada with three facilities. In the year ended Dec. 31, 2006, Western Air had revenue of $59.6 million.   ; Ferguson has also acquired Davidson Pipe Company Inc., a pipes, valves and fittings distributor in the New York metropolitan market. In the year ended Sept. 30, 2006, Davidson had revenue of $125.8 million.   ; Ferguson is a company of Wolseley plc, a global distributor of plumbing and heating products as well as building materials. Wolseley announced five bolt-on acquisitions this month, including one by Stock Building Supply and two in Europe. These acquisitions are expected to add 110 million pounds  ; to total revenue.