I performed a single system heating maintenance on a 2023 gas system. I checked amps, capacitors, flame sensor, pressure switch, burners, safeties, and cleanliness. The system is performing to manufacture specifications. I proposed 2 recommendations: air scrubber to help keep the system clean and treat the air. A surge protector to help protect the indoor equipment from shorting out from a power fluctuation. Customer was working and unavailable at the end of the call.