Use a gauge and start with 1/2 can - then run engine with AC on high for 3 minutes and then check gauge
buy the can with the guage, the gauge haves an indicator, that will indicate the correct (safe) amount.
The R134a professional manifold gauge or gauges uses three hoses that each connect to the low and high ports of an AC system. The remaining hose connects to the can refrigerant. Use the gauges to check for leaks and see how refrigerant is need to refill the freon.
Take it to an A/C shop.
Go to autozone and get a manifold vacuum ac gauge for R134a. Ofcoarse, also pick up a can of R134a. Hook up the gauges to the valves on the AC hoses. Add the refrigerant but watch the pressure on the gauge!! Any good manual will tell you the max pressure for the system.
It is necessary to read the density and the quality of the gauge. You should see the lower side.
R134a is a refrigerant gas
25 gauge is the size of the needle not the syringe. they are measured in cc's
Can you mix r134a with r410a?
The gas gauge on the truck read 70 miles per hour.
It would be better to write: My gas gauge reads empty. Note that 'gauge' is singular, so it needs the singular verb, reads. If you had several cars all with gas gauges that read empty, then the verb would be read.
An air gauge measures pressure relative to the atmospheric pressure, while a water gauge measures pressure relative to its own density. Water is denser than air, so the air gauge reading will be 3 times higher than the water gauge due to the difference in reference points for each gauge.