A/C Pressure problem - Low side too high

[Acrisoft]

Hi

The a/c system was evacuated and added R134

Low pressure side 70PSI ( too high) and high pressure side 140PSI (too low)

Can it be excessive refrigerant load ?

Compressor is running all time (non-stop)



Moises

[andywill]

I assume your talking about car A/C and it sounds very much like your compressor is not pumping.......

[nike123]

Rise your engine RPM and then measure pressures!

[andywill]

You have to take into consideration that he is in Brazil which is about 30C ambient, and with a suction pressure of 70 PSI I would expect a discharge pressure well in excess of 140 PSI.

[Shibhrac]

If you are talking about car ac system i would say that if everything is normal the suction pressure should not exceed 35 psi in the start up and will get lower when the temp. Is getting down or the the speed of the compressor is getting high. The said pressure means that the compressor is not pumping.

[Acrisoft]

Yes, it`s aumotive system
I contacted him now and he said when he turns the compressor off, the low side goes to
about 150PSI and also high side 150PSI

Sorry for inaccurate information, and thanks in advance for efforts. I am not specialist, just a mechatronics teacher trying to assist my student which is far away from me

[nike123]

[
Yes, it`s aumotive system
I contacted him now and he said when he turns the compressor off, the low side goes to
about 150PSI and also high side 150PSI

That is normal and it tell us that ambient temperature is 40°C (105°F) if you telling us absolute pressure or 44°C (112°F) if you giving us relative pressure.
What pressure you are giving to us, relative (gauge with -15,4psig at low end) or absolute (gauge with 0 psia at low end)?

[Acrisoft]

Thanks

Problem was really the compressor

Temperature is 25C to 27C and pressure gaugue not sure. Maybe more common type