I performed a single heating maintenance on a 2015 heat pump system. I checked amps, capacitors, filter, electrical connections, cleanliness, and safeties. Also, I removed leaves from the top and around the sides of the outdoor unit. I failed to take a picture afterwards. I discovered that the blower has a substantial amount of build up present. This causes higher electric bills and added wear on the motor. I noticed that the unit does not have surge protection either. I presented solutions to the customer, and he declined at the time of service. The system is heating upon departure.