As a very first step, have you tested the A/C to make sure it’s cooling to specification? Discharge air should be between 15~20 degrees F cooler than what’s going back into unit, normally assumed close to average temperature in RV.
If temperature difference is much colder, that can also signal a problem like insufficient air flow. If air temperature drop is too low, like say 10 F, it suggest unit is not delivering cooling capacity because of other reasons, like maybe low on refrigerant.
Just out of curiosity, do you notice a big difference when parked in shade versus parked in direct sun? It doesn’t take much sun through windows to overpower an RV A/C.
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