I'm a newbie tech and I am stumped over a unit that I was trying to service. The unit a rudd model #uka-060 JAS, a 5 ton unit manufactured 1/93 hooked up to matching 5 ton capillary tube metered coil. According to the homeowner they had a tech fill it up with refridgerant last year when they first started having problems with the unit and it is still not working properly.

The following readings were taken on a 87 degree day aproximately 50% humidity with a indoor temperature of 82 degrees. Low pressure 62psi @ 65 degrees superheat=30 degrees, High pressure 330psi @ 90 degrees sub cooling = 40 degees. inside temperature differential aprox 14 degrees.

At first I suspected a dirty evaporator coil so I took it apart to check it and that wasn't the case while I was in there I took a few temperature measurements after the metering device it was 42 the middle was 47 and near the suction line it was 62 degrees. I had also cleaned the condensing coils as well but not improvement either. I was tempted to add more refridgerant but the high side pressure seems high already. There was no charging table so I am not really sure. I would like to charge to about 15-20 degrees superheat and about the same amount of subcooling. I am suspecting there may be some restriction but I cannot be certain.

Thanks in advance,