Performed routine maintenance on 80% furnace, check amp draws of both blower and inducer, both testing within factory range at this time, checked filter upon request, filter looked good, instructed on filter changes. Igniter tested within range, cleaned flame sensor, both operating correctly at this time, burners were clean and free of debris, as well as pressure switch hose. Temperature split between supply and return tested within range. Furnace in garage and insulated property. Gas pressure tested perfect.