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Discussion Starter · #1 ·
I have a question about my AC system. I live in California so the relative humidity is next to nothing, today it is 13% and the temperature is 105. I checked my AC system and the High PSI was just over 300 and the R134a reading was at 160. The low reading was 70PSI and R134a was 70 as well.

Is this good or bad? If bad any ideas on what is wrong?

Thanks for all suggestions.
50482
50483
 

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do why are you checking the system in the first place? is there an issue? whats the temps at the vents? does your engine temp run hot? does your ac compressor clutch cycle on/off frequently?

high side is much to high in my opinion. you might have a blockage somewhere in the system. could be a leak where air or other debris has been sucked in casing bits to clog up the condenser.
 

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Discussion Starter · #3 ·
It is not as cold as it was last season. I will have to check the temperature at the vent, just going by feel at this point. The engine does not run hot unless the vehicle is idling sitting still, like over 2 hours, the AC was running and it was around 102 outside. Have leak check fluid inside and no visible leaks. Is there a way to check if the condenser is clogged? I will check and post the temperature at the vent.
 

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all HVAC systems will leak at some point. i would first verify you have no leaks in the engine room before proceeding to fix anything else.
 

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The best way to check you A/C for proper operation. Is on a HOT day... roll all your windows down and turn the A/C to MAX or lowest TEMP possible. Then check your pressures. It's advisable to raise the engine RPM to at least 1500. All these step ensures your A/C compressor is running at top output. Check and make sure all your electric fans are running. Otherwise those pressures look normal. You may have climate control issues.

I know a lot of folks do this... but the worst thing for an engine is to run on idle with A/C On.
 

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Normal system pressures at 105 degree ambient temp would be: Low side 50-55 and high side 330-335. You need to check the temp at the vents. drive the vehicle and get the interior comfortable and use a thermometer in the vents. There is no set temp for air blowing from the vents. It is the differential that matters. So the air going coming out of the vents should be 16-22 degrees colder than the air going into the evaporator. Remember AC is more efficient when humidity is highest. So with low humidity even your home AC may seem like it’s not working well.
 

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There is no set temp for air blowing from the vents. It is the differential that matters. So the air going coming out of the vents should be 16-22 degrees colder than the air going into the evaporator. Remember AC is more efficient when humidity is highest. So with low humidity even your home AC may seem like it’s not working well.
So while driving check your Beast's outside air temp...that will be about close to what is going into the evaporator. Then compare that to the temp reading you are getting from your vents. the difference should be as noted by @DennisC
 
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