Went for a tune up call today for heat. Tested for static pressure system is passing when in heat. All electrical components are passing for manufacture specifications. Did a combustion test is within range. Inspected heat exchanger no cracks/leaks were detected. However did find heat stress on unit and some rust points on the heat exchanger. Checked temp split and is passing for specifications. Did replace filter for customer that was provided. Cleaned flame sensor and pressure switch hose. Did check humidifier is currently operating. Would recommend replacing water panel and System is up and running before departure. Thank you for choosing LBA services-Johann