Knox County commissioners gave unanimous approval Tuesday, Feb. 20, to spending nearly $2.2 million to replace the heating, ventilation and air conditioning system in the older part of the courthouse building.

The work is expected to begin May 1 and take four to five months to complete, according to Knox County Administrator Andrew Hart.

The current heating and cooling system is nearly 30 years old. Commissioner Richard Parent Jr. pointed out that the chiller for the system runs all year round.

Siemens Industry Inc. will finance the upgrade and the county will repay the costs over 15 years. The most recent interest rate quote on the repayment was 3.56 percent, and the rate should be locked in by the end of the month.