Upon my arrival, I evaluated two Carrier gas furnace systems. Found unit number one to have a faulty air movement system as well as a faulty flame safety sensor and could not complete evaluation. Customer chose option for repair and we will be returning to replace air movement system and flame safety sensor. Unit number two was performing to manufacture, specifications, tested safety and performance, and changed filter supplied by customer. Unit number two needs small ductwork repair, will perform repair when we return for unit number one air movement system and flame safety sensor replacement.