In the event of an ongoing operational problem such as persistent fouling or plugging, excessive leakage, corrosion, erosion or a specific component failure, Air Preheater Company has a staff of qualified field engineers on call to provide assistance in diagnosing the root cause of the problem and recommending the appropriate interim repairs and permanent corrective actions. In preparation for a fuel or other operating change, our engineering staff is available to assist with the evaluation of performance and cleanability issues which may arise.  Often, a comprehensive air preheater test can provide valuable information regarding the potential for unit upratings, fuel changes and other system changes under consideration.