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pETER, Technician
Category: Car
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Guages..correct pressures adjusting for outside temp..too low

Resolved Question:

I need toadd freon to my car but do not have a machine to measure freon I need to use guages and pressure readings I have a chart that shows correct pressures adjusting for outside temp and humidity but I need to know what will the guages show when the car is low on freon will the low side be too low and high be too low if it is low on freon and what will show if it is overcharged
Submitted: 5 years ago.
Category: Car
Expert:  pETER replied 5 years ago.

Hello you know if you have the R12 or the R134 system ?

Does the AC compressor come ON ?

Usually ,with 80 F outside temp.the correct readings should be : the gage on low side should read 40 to 45 psi and the High side should be 200 t0 225 psi

Let me know.

Thank you.

Customer: replied 5 years ago.

I have a chart that shows correct readings I need to know how to diagnose if a system is over or under charged. In the numbers you used if the system was low on freon would the readings be 30 low side and 180 high side and what would example readings be if overcharged

Expert:  pETER replied 5 years ago.

An overcharged system will show both sides numbers higher then the specs.

You need to charge it if both numbers are lower than specs.

If the low side is high and the high side is low you may have compressor failure.

I if the low side is low and the high side is higher than normal,you may have blockage on the system.

good luck.

thank you.

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