Return and Supply Solution AC Diagnostic System:3rd/4th floor Refrigerant Type R410A Metering Device-TXV SP/HP124.7/342.1 SLT/LLT57,6/99,7 VSAT/LSAT42,6/105 SH/SC15/5.3 Outdoor Entering Air Temperature 85 Filter Size(s)20x25x4(2) Returned tstat to original settings: Y(74) New Honeywell t6 thermostats Unit operational; prior to leaving: Y Static pressure readings 3rd and 4th(bothzones) Furnace cabinet .24/furnace supply .61/supply plenum.32 1st and 2nd Furnace cabinet .22/furnace supply.72/supply plenum .4 Notes:follow up visit to complete install work. Installed two new return plenums, new transitions with second media filter to increase airflow back to the unit. For the third and fourth floor system we had to re route the copper lines going to the evaporator coil to accommodate for the new transition and media filter. Replaced supply plenum for the 3rd and 4th floor unit due to large amount of organic growth due to airflow issues and attic air mixing with conditioned air. Added 2