Performed preventative maintenance for gas furnace installed by us in 2018. Inspected all the electrical components. Replaced the batteries in the main floor zone thermostat. We replaced the Merv 11 air filter (16x25x5) in the spring 2022. Tested the amp draw for the blower and inducer. Both are operating properly within the manufacturer specs. Confirmed proper high and low voltages. Tested the electric zone damper system for the first and second floor thermostat. Performed a combustion analysis on the furnace. System is operating at 83.7% efficiency with a CO level of 13ppm. System is operating properly at this time. Customer asked for senior discount. discount is approved by TD and applied to invoice.