[mfiazzo]

Hi Mark, the low pressure should be around 30 psi at 90 degrees.

Did you purge the line before you installed it? Sounds like you may have some air in the system. Can you find a sight glass near the condenser? If you can, turn on the A/C and look at the sight glass, it should be running clear. If you see bubbles, could be low on freon or air in system.