HVAC Diagnostics Simplified Unraveling High vs. Low Pressure Ports

I can't help you on which is the high or low side. Your a/c system ... My question is ...from the firewall is the low pressure port on the driver ... Well the low pressure is in front of the manifold and the high is on the passenger side of the bay, plus the port sizes are different, so it's ... The compressor initially began pulling the low side down to 30 psi, then began to climb in pressure and would cycle off around 70 psi. Very high on the high pressure side and low on the low pressure side. First check to see if the condenser fan is running at full speed. If ... With the engine off and sitting for a while, both high and low should be about the same. Roughly the same pressure (psi) as the outdoor temperature in degrees ... The extremely high pressure on the high side and normal pressure on the suction side indicates that the evaporator is overheating. According to the parts diagram, the low pressure port is in the liquid line, over by the SBEC. It shows the high pressure line on the ... The compressor creates high pressure by compressing the low pressure vapor from the evaporator so that the high pressure vapor can release heat at the condenser ... The typical low pressure side PSI is between 20 and 50, so 70 is on the high side...although not likely dangerously high. If you're not getting ... The high side of the system is the smaller of the two. And on a 134a system the low side port is the bigger of the two. Hope this helps. A.