Upon arrival inspected Bosch indoor head for kitchen area. Air movement system could be heard louder than normal. Inspect blower wheel and undercarriage. Heavy dirt accumulation on blower wheel. Inspect to see if any obstruction was causing noise @ wheel. Wheel is free of obstruction. Noise will increase when fan speed is adjusted. System is still operating to provide customer with heat. Recommended to customer to have deep clean and rejuvenation done on kitchen indoor head to see if there’s any obstruction that we can’t visually see @ time of inspection. Unit will be broken down upon deep clean recommendations. Possibility of wheel alignment being off. Rubber housing is worn based on age and or other issues with air movement system. 2 tech is needed. 1-2 hours needed to complete task. Office to follow up with customer. View visual findings from this job here - https://visionshare.xoi.io/?id=XA-A243-0E645CA9B5904BC28339DC4170DBEFFB Customer is aware that 2 tech is needed to break unit