Auto Air Conditioning & Heater Repair: large truck ac, ford style, kenworths

Question
99 international 9900.3406 cat engine. standard Ford style ac compressor. ac works but does not get cool enough. have replaced compressor, drier,
expansion valve, hi and lo switches. no leaks.clutch  functions properly,system purged and vacuumed . hi/lo side pressure 55/250 during operation. any ideas?

Answer
Your low and high side readings are too high.Shoot water over the condenser and see if the psi. drops.you may have a cooling problem. another concern is the system may be overcharged-double check the charge amounts.Normal readings at 1200rpm should be 25-35psi-low / 180 to 210psi-high side..Should pull vaccum for 1hr. min.

Good luck,davidt

ps I`ve done Kenworths and Peterbilts and got them into the lower 40`s.