I am working for an apartment complex. Just recently started. They are losing compressors at the rate of about two a week. Less than 5 years old. They have been installing 2 ton Goodmans without changing out the evaporator coils. The units don't seem to cool very well. Temp diff. is only 11 to maybe 15 degrees across evap. coil. 2 things got me wondering... The evap. coils are 2 and half....and the liquid line is 5/16. From the original installs. The goodman condensor specs call for 3/8. Could this be the reason they aren't getting any efficiency?