The house is cool and still feels clammy.
Temperature is only half of comfort. In monsoon season the other half shows up.
For most of the year Phoenix is dry enough that nobody thinks about humidity. Then monsoon arrives, dew points climb, and houses that were comfortable in June feel clammy in August at the same thermostat setting.
The thermostat only measures temperature. Comfort is temperature and moisture together, which is why a house at 76 can feel worse in August than it did in June.
How an AC dehumidifies
As a side effect. The evaporator coil runs below the dew point of the air crossing it, moisture condenses on it, and runs off into the drain pan.
That removal only happens while the system is running. The longer the run, the more moisture leaves. Which gives you the central fact: anything shortening your run times makes the house damper.
Why oversizing is the usual culprit
A system with more capacity than the house needs hits the thermostat setpoint quickly and shuts off. Temperature satisfied, moisture barely touched. The house ends up cool and clammy, which is the exact complaint.
Nothing is broken. It was specified wrong, and no part replacement fixes it. Worth knowing before somebody sells you components.
If that is your situation, the practical levers are a slightly higher setpoint with longer runs, a lower fan speed on the cooling stage where the equipment allows it, and a portable dehumidifier in the worst room through monsoon.
The other causes worth ruling out
Short cycling from a fault rather than from sizing: a dirty coil tripping a safety, a bad thermostat location. Same effect, different fix, and these ones are repairable.
Fan set to ON. This one actively makes it worse. With the blower running continuously, water sitting on the coil after the compressor stops gets evaporated straight back into the house. Set it to AUTO.
A plugged drain. Water that cannot leave the pan evaporates back into the airstream, and it also smells. The drain line guide covers it.
Outside air getting in. Door seals, an open fireplace damper, a bathroom fan running for hours, an attic hatch that does not seat.
What a visit measures
Delta T across the coil, run times, airflow, and whether the drain is actually clearing. Together those say whether you have a fault that is cutting runs short or a system doing exactly what an oversized system does.
The second answer is not what anybody wants to hear, and it is cheaper than buying parts that will not change anything.
Questions that come with this one.
Does an AC remove humidity?
Yes, as a side effect. Moisture condenses on the cold evaporator coil and drains away. That only happens while the system is actually running, which is why short run times leave a house cool and damp.
Should I set the thermostat lower to dry the house out?
It is the wrong lever and it works by accident: a lower setpoint means longer run times, which removes more moisture. The better answer is to fix whatever is cutting the run times short, because that costs less to run.
Would a dehumidifier help?
In a badly oversized system, a portable dehumidifier in the worst room genuinely helps and costs little. It is treating the symptom, but monsoon is a few months and a new system is not a small purchase.
Other things that go wrong.
What an AC tune-up actually includes.
Three different visits, three different prices, and a plain list of what separates them.
Read itComing back for the season.
The house sat at 85 for five months with nobody in it. Here is what that does to a system, and what to sort out before you arrive.
Read itYou are watching the house and the AC stopped.
Not your house, not your call, and still your problem for the next few hours. Here is the order to work in.
Read it