I have two Carriers insatlled in 1999 via builder. Not sure of seer but I'm sure it was no more than they had to install.
They sit on the west side of my house and get unobstructed direct sun. WE have already seen 95-98 temps this week so it gets hot.
Does installing a solar screen above and in front of these units make sense? Some claim to block 90% of sun heat. Being a screen I would assume air flow would be ok especially if I left space in front and on top.
The goal would be to lower the High Pressure PSI and thus current draw. Would the savings be rounding error in my utility bill or something more? (Units HP PSI is typically 275 @ 95 degree outside temp, 225 @ 80 degrees of so, condensers and sytems are clean with about 25 degree delta between intake (78 typ) and outtake (52-53 typ) indoor temps
A solar block is a good idea as long as there is plenty of clearance for airflow. And it's not just the condensers that need to be shaded. The surrounding ground and house are also heating up and raising the ambiant temperature of the air being drawn through the coils.
The best solution would be to plant some trees to provide the whole area and your house with shade. That way, your house will have less solar heat gain, so your AC would have to run less.
if space allows.
you could have them moved to the east side. Only if its practical. I have moved a few for that very reason.