Originally posted by vapor_rush
What does it do to upsize an indoor evap coil.
Example: 3 Ton condenser
4 Ton Evap coil
Does this increase the Seer rating?
In many cases yes, many higher SEER units have a larger indoor coil, provided the manufacturer lists the coil/outdoor unit as a match.
Do you have to change the orifice size?
Yes, if it has a fixed orifice metering device it must be sized to the outdoor unit