How much refrigerant/freon?

[Chillin014]

Don't have the sticker any more on my evaporator core box and the mechanic only put in 2 pounds yesterday. He said the gauges showed full and he was afraid to put any more. Well its not blowing very cold and I found a decal that reads the system needs more like 3.25 pounds. Does this sound right?

here is the decal:

thank you

 

[pontiacgp]

ac question from someone with the name chillin is appropriate I guess... :lol:

Did he fill it with R-12?....that stuff is expensive. Did he evac the system before filling it and how old is your evaporator.

 

[Chillin014]

hahah nice one. Everythign is brand new except the evaporator core. He did evacuate it, there were no leaks during the vacuum test. My cheapo 4-month old a/c compressor died and I bought another one so I'm having him re-fill it but we couldn't remember how much R-134 (or whatever it is) he used last time. It blew much colder with the old noisy compressor though...

 

[megaladon6]

no offense, but if he was a good mechanic, he'd look up the pressures and fill it so they are correct. that's the correct way to do it as NO ONE outside the factory has the proper equipment to go by weight. and there's always "leftovers" in the system that affect the weight.

 

[Shibbs]

My 82 ElCamino took 3.2 lbs of R134a + some oil for it to cool properly. But yes, your mechanic SHOULD be able to look up the correct amounts for your car.

Alldata has the correct amounts.

Remember - if your R12 sticker reads 3.75 lbs, you do NOT want to put in 3.75 lbs of R134. I know you should put in less, but not sure on how much less. As I said, at my elevation and temperature, 3.2 was the magic numbers for me.

 

[trog]

usually 80% by weight 134 to r12

 

[Chillin014]

Okay, yeah I was also considering the r12 weight may not be the same as the r134 but if 80% is the rule of thumb it sounds like I need at least a pound more. 2 pounds just seems way too low. I'll talk to him about it tomorrow. Thanks.

 

[pontiacgp]

the gauges will you tell you when the system is full....trying to guess how much you need will increase the pressure on the high side enough to blow the line if you put too much...don't ask me how I know...

 

[Chillin014]

I dont know how to read the gauges, but he does. For whatever reason he felt like it was full though and was "afraid" to add more. But the system was completely evacuated before putting in 2 pounds...so...I'm not sure why the gauges were reading "full".

 

[Chillin014]

Took it into the mechanic today and he looked it up on his computer and found "3.25 lbs" to be the spec. We put in the necessary amount and it blows as cold as ever.