Routine maintenance of my AC, Tech checked pressure and in house air temp. He said the charge is a little low, so he added a little freon. He said I got 17 degrees in house temp split, everything looks good. But when he checked the line pressure, I saw 80 on the low meter, 280 on the high meter. Isn't that a little too high ? I heard the normal numbers should be 70 and 200. WHy did he say every thing looks good ? By the way, I have a 3 ton Goodmen, 8 years old, today's outside temp is 95F.
From what I have read 40% of hvac systems are not properly charged. I use an electronic superheat/sub cooling meter and the proper factory chart to do a fill within 1 degree of needed charge. Meter reads out super heat directly ands allows adding or removing the right amount of charge.