i went to do PM on a 6 or so house in the same sub division.
All of the houses are built by the same builder known for "Most House for the Money".
All the 6 houses uses the same exact tonnage and equipment no matter the size of the house.
2 stories 1250 sqft . would have 2 x 1.5 tons units
2 stories 1800 sqft no basement would have 2 x 1.5 tons units.
a 2200 sqft + 900sqft basement also has 2 x 1.5 tons units .
this house AC Almost never stop working in the day time according to the owner. and Inside house temp doesnot go down below 75deg.
The house has cathedral ceiling and HUGE glass windows facing west.
On last house i can only wash the outside coil, inspect the inside coil . make sure filter is good . no obvious ducts leak that i can see.
proper charge using Superheat ( Wetbulb is very low since humidity is low due to the AC working all day long) and recomend the owner to call s back when the current units finaly die.
First house a 1250 sqft 1.5 story. Upstair has a 2 small bedroom and bathroom. and a 1.5 tons unit. the owner still install a window shaker on one of the room that face west. Insulation on the attic is woefully in adequate.
Builder must also use a HVAC contractor that order 1.5 tons unit by the warehouseful. 1.5 tons is all that they use in every single house no matter what size