While servicing an automotive AC system, a technician can expect the low-pressure gauge reading to typically range between 25 to 45 psi under normal operating conditions. However, during recovery or when the system is off, it can drop as low as 0 psi if the system is completely evacuated. It's important for the technician to refer to the specific vehicle's service manual, as pressure readings can vary based on the type of refrigerant and the system design.
To calculate absolute pressure when a barometer reading is given, simply add the barometer reading to the atmospheric pressure at sea level, which is approximately 101.3 kPa or 14.7 psi. This will give you the absolute pressure at the specific location where the barometer reading was taken.
Gives a reading of what the pressure in the system is.
Low pressure
Arterial pressure
To check the refrigerant level in your AC system, you will need a pressure gauge. Attach the gauge to the service valve on the AC unit and compare the reading to the manufacturer's recommended pressure levels. If the pressure is too low, it may indicate a refrigerant leak. If you are unsure how to do this, it is best to contact a professional HVAC technician for assistance.
Allowing the recovery cylinder to stabilize to room temperature before taking a pressure reading is important because temperature affects pressure readings in gases. If the cylinder is too cold or too warm, the pressure may not accurately reflect the contents, potentially leading to incorrect assessments of noncondensables. Stabilizing at room temperature ensures that the pressure reading reflects the true state of the refrigerant and any noncondensables present in the cylinder. This practice helps ensure accurate measurements and safe handling of the cylinder.
gauge pressure
air pressure
I'm not a mechanic / technician but I've heard of a plugged PCV system ( valve, hoses etc ) blowing the oil dipstick up off its seat - but I don't know if that raises the oil pressure reading on the gauge ? ( of course , there is a normal change in oil pressure from idle as the RPM's go up - to a point )
Second
Air pressure
NO it will not.