Limiting point?

[rhgindc]

I just had a 2.5 ton Rheem heat pump a/c unit put in my commercial suite to replace an old one. I've set my thermostat in the office to be 72 degrees. But, in Southern California its gotten very hot the last week or so, getting up to 100-105 degrees at times.

The lowest the temperature gets in my office this week as been 75-79 degrees even though my thermostat is set for 72 degrees. My office is 800 sq. ft. I called the HVAC shop that installed the new unit. They said it won't get down to the value set on my thermostat because there's some sort of "set differential" between what the temperature outside reaches and what the unit will cool down to inside. In other words, there seems to be a 'limiting value/point' based on the outside tempature. Is this true? Or is there something wrong with my new unit?

[duke of earl]

Someone's feeding you a spoonful of _ _ _ _!Sounds like someone didn't dial in the refrigerant charge or left off a panel on the air handler and you're sucking in attic air into the evaporator coil.Could be other things but I would look at these first.

[Control Man]

Could have a INDOOR / OUTDOOR reset , gives you a 10'F - 25' F supply air differential from outside to inside air temperatures. Saves ENERGY in areas that are on the verge of BLACKOUT as so many think they need 65'F space temperatures when its 100'F + outside.