I would like to know what my AC pressure on the low side should be in summer?

Hello, You will need to use a chart for this. There are pressure charts that indicate pressures according to the ambient temperature, and without that you can only guess if it is ~about right. Something you should know, only check pressure with the vehicle running, as the high and low side will equalize in pressure while the engine is off. Also, the low side should not be close to the high side while running, and there should be a significant change when the A/C starts and cycles.