I have an 86 IROC carbureted v8, it was already converted to R134 when I bought it, presently it does not work ( not cold ) the compressor comes on then turns off, ( Low Pressure ) I am going to replace the O-Rings then evacuate the system completely then recharge the system with oil and Freon, my question is what are the High and Low pressure reading supposed to be set to? I am curious what you guys and gals have found to give you the coldest output??

P.S. A friend is a certified A/C Tech and will properly evacuate the system for me.

Thanks,

Fran

 

you wont ever have "cold " using 134 in a 12 system.cool maybe,but the warmer it is outside the less cool you get.sorry to break it to you .but the 12 systems don't like 134 at all. im going with "hc12-A"

 

Pressure readings only please

 

i have a r12 system converted to 134 and it gets cold. I am in oklahoma and it gets very comfortable inside in the high heat. If you want freakish cold like sub 40s then I would look into some other options like rusty is talking about.

I think the system takes like 3.5 lbs or something. I believe there is a tech article that has the exact capacity. I just bought cans from the store and used their recommended pressures. You can always do it the wrong way and fill it until the hi-pressure switch is tripped and cuts off the compressor then let some out until it comes back on.

 

Please understand the answer you are seeking isn't the question you're asking (or vice versa).

Pressures are relative to Ambient Temperature, Relative Humidity and Refrigerant Charge at the time you are taking the Pressure readings. A more appropriate question would be how much refrigerant does the system require. On a sidenote, unless you had a rapid release of refrigerant, just replaced a component in the system, or flushed the system then you don't need to add more oil to the system. You'll end up overcharging the oil and at a minimum you will have poor performance and in a worse case scenario you'll grenade your compressor.

I would leave it to your friend to get everything set for you.

 

Hay folks,

I am simply asking for gauge reading I should set my a/c at, but all I see is comments that have nothing to do with the question? It strikes me that the comment show that you do not know the answer, and that is perfectly fine. When you chime in with erroneous answers it muddy's the waters for me and others that use the search function.
How about this for an answer:

Deg F------------- low pressure------High Pressure

65------------------25-35 psi---------135-155
70------------------35-40 psi----------145-160
ect

HMMMMMMM if you cant answer the question maybe, Just Maybe your input is not needed.

P.S. If you are a senior member maybe the next time you ask someone to use the search function you will now understand why they cannot find the answer they are looking for, and yes I did do a search and found comments, but no answers.

I know this sounds krass but lets try to help each other and not antagonize each other.

 

Sorry there is no pressure reading that indicates a correctly charged system......What you are asking is laughable at best....I do not mean to come off sounding like an ***. You came in and asked an unreasonable question. A R12 system will never cool correctly with R134a.

 

enough said??