# AC Low side Over Pressure



## Reset (May 1, 2019)

I have a 2009 Rogue, just over 100K miles. The AC cut out, fan and compressor not turning on. Thought refrigerant would be low from a leak, but when I checked the low pressure port it was way over pressure. The system has never been touched, so not like too much refrigerant was added. Does anyone know what causes this? Trying to confirm if it is the compressor or not, hoping it's a clogged line instead. Also, electrical checks out. Thanks.


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## rogoman (Dec 16, 2004)

How are you measuring the pressures; are you using the little gauge on the refrigerant can. You should be using a manifold gauge set to measure both sides. What are the actual low and high side pressures and what is the outside air temperature. Pressures can vary considerably according to the outside temperature. Get a reading on the high/low pressures and the outside temperature, then post your findings here so that we can analyze the possible cause to your problem.


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## Reset (May 1, 2019)

rogoman said:


> How are you measuring the pressures; are you using the little gauge on the refrigerant can. You should be using a manifold gauge set to measure both sides. What are the actual low and high side pressures and what is the outside air temperature. Pressures can vary considerably according to the outside temperature. Get a reading on the high/low pressures and the outside temperature, then post your findings here so that we can analyze the possible cause to your problem.


Yes, all I have is the guage on the refrigerant can. I was looking for the manifold guage as a loaner tool, but doesn't seem to be available. Not worth purchasing one, so maybe it's just best to take it in and get a proper diagnosis. I can do the compressor easily enough, and let the garage properly fill the system.


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## rogoman (Dec 16, 2004)

I'll post a little chart here for comparisons when you go to the shop:


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## smj999smj (Jan 1, 2006)

If the compressor is not turning "on," then the low-side pressure would be high because you are reading static pressure, rather than operating pressure. Static pressure with a full system is usually around 70 PSI or close to the ambient temperature.


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## Reset (May 1, 2019)

Thanks for the input, I know I let this go. Going to take it to the dealer and let them diagnose it. If I can fix it myself, great. But would rather someone with the proper tools at least figure it out.


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