Went for a maintenance call today for heat. All electrical components are passing for manufacture specifications. Did a combustion test is within range. Inspected heat exchanger no cracks/leaks were detected, but did noticed some heat stress in heat exchanger.Checked temp split and is passing. Did leave pack of filter for customer. Cleaned flame sensor and pressure switch hose. Checked humidifier water panel is good. Checked up bulb and does need to be replaced. Customer approved of getting filters, did drop them off. Renewed membership and UV bulb will be installed tomorrow. System is up and running before departure. Thank you for choosing LBA services-Johann