Diagnostic inspection on two rooftop systems. First system tested was #5. Inspection of unit showed no issues at this time. Air temperatures, and refrigerant temperatures were measures within spec. Did not witness any icing while testing. Second system tested was #2. System ran in cooling with a high air temperature drop of ~27F. Attempted to adjust motor pulley to increase airflow. Adjusted pulley as far as possible with not much change due to pulley being difficult to adjust due to age and rust. Current temperature drop with pulley adjusted as far as possible is 23-25F. Pulley should be replaced along with a new A61 belt. New pulley will be able to be adjusted further. Pulley size 4 3/4in with 7/8in shaft. May need a proper pulley puller to remove old pulley. Air filters are mostly dirty and should be replaced to help with proper airflow. Both systems are running in cooling at this time.
