The two large steam boilers that provide heat to the eight main buildings on the Barton Community College campus are now 50 years old, Vice President of Administration Mark Dean told college trustees. On Tuesday, the board approved his recommendation to replace one boiler with three small, high-efficiency boilers.The boilers and equipment will cost $172,720, while installation and demolition of the existing Boiler No. 1 will cost $156,650.The new boilers are expected to save 30 percent on the cost of gas necessary for campus heating, Dean told the board.