Went to a system today,low side pressure was 90 psi. Warm air coming out of registers. Newly installed system,don't know why HO didn't call the company that installed the unit. Lowered suction pressure to 70 psi.,should have a 40 degree coil correct? Suction line at compressor was sweating a little,temp. was around 55. Probably a little less didn't get that accurate of a temp. Went in house and temp. out of registers was 60 degrees. 84 air temp. in house. HO called back and said not cooling enough. Unit is cooling second floor and 2 attic rooms,large open stairway to downstairs that is not air conditioned. I could feel cool air coming downstairs as I walked up them. If you have to add R22 to system because of a long run,this is not a long run,the pressure should still be around the 68-70 suction line shouldn't it?