My temperature difference between my supplies and returns is only around 5 degrees F. I opened up my air handler to see if the evaporator coil was dirty, and it was clean -- but running the outside unit (condensor) without running the air handler, I expected the evaporator coils to get very cold - to ice up, right? Well they got cold, but nowhere close to icing, and I suspect that's the reason my delta-T is only around 5F.
So this is after I just had the refrigerant completely recharged -- what could be any other issues as to why the coil isn't ice cold?
Edit: I've cleaned the condensor fins already. The whole system is around 20 years old (I know, it's ancient)
Edit: I had the HVAC guy come and check. I'm at 25 psi on the lines, so yeah I have a leak. Not sure why he didn't see the leak before. Waste of money though.