A 23-year old 5-tower RTO excelled in its official EPA test after a troubling start. During the first test, two outputs failed on an 120VAC output card, resulting in the failure of two purge dampers to function properly. Even with this, the unit achieved a 98.987% Destruction Rate Efficiency. RHZ quickly found and fixed the problem. This involved wiring and programming. It took RHZ less than an hour to troubleshoot and correct the problem.