refrigerant question
- Thread starter yonyon
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Kestas
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I'm not an expert on all refrigerants, but I would expect a static pressure of 40-60 psi for common refrigerants. 320 to 350 psi sounds like serious overfill, likely by an amateur.
This was found in a car that's supposed to have R134a in it. I was a bit curious as to whether this might have been charged with some incorrect refrigerant. If there's nobody here who knows of anything offhand I'll take it to mean there isn't anything common and the system was just filled with gas possibly for a leak check.
Originally Posted By: yonyon
This was found in a car that's supposed to have R134a in it. I was a bit curious as to whether this might have been charged with some incorrect refrigerant. If there's nobody here who knows of anything offhand I'll take it to mean there isn't anything common and the system was just filled with gas possibly for a leak check.
Someone could have installed the wrong refrigerant, or overcharged with R-134a. You would need a refrigerant gas detector to know.
R-12 and R-134a are supposed to have 30-40 PSI on the low side,
I had an auto teacher who found someone who thought if an auto A/C system failed, it just needed more refrigerant. 8Lb of refrigerant was used in a car that might take 2.5LB MAX.
Sometimes someone would run R-22 in an R-12 system. That was because mineral oil would remain in the system, and an R-134a conversion would require ester or PAG oil. Unfortunately, the system pressure would rise so much, that it would destroy something in the A/C system.
This was found in a car that's supposed to have R134a in it. I was a bit curious as to whether this might have been charged with some incorrect refrigerant. If there's nobody here who knows of anything offhand I'll take it to mean there isn't anything common and the system was just filled with gas possibly for a leak check.
Someone could have installed the wrong refrigerant, or overcharged with R-134a. You would need a refrigerant gas detector to know.
R-12 and R-134a are supposed to have 30-40 PSI on the low side,
I had an auto teacher who found someone who thought if an auto A/C system failed, it just needed more refrigerant. 8Lb of refrigerant was used in a car that might take 2.5LB MAX.
Sometimes someone would run R-22 in an R-12 system. That was because mineral oil would remain in the system, and an R-134a conversion would require ester or PAG oil. Unfortunately, the system pressure would rise so much, that it would destroy something in the A/C system.
Originally Posted By: artificialist
Someone could have installed the wrong refrigerant, or overcharged with R-134a. You would need a refrigerant gas detector to know.
It wasn't R-134a. Whatever it was, it weighed about about 2/3 as much as the specified amount of R-134a but had a [censored] more pressure and floated on top. It was probably just some helium or argon or some such that someone forgot about.
Someone could have installed the wrong refrigerant, or overcharged with R-134a. You would need a refrigerant gas detector to know.
It wasn't R-134a. Whatever it was, it weighed about about 2/3 as much as the specified amount of R-134a but had a [censored] more pressure and floated on top. It was probably just some helium or argon or some such that someone forgot about.
Originally Posted By: yonyon
Originally Posted By: artificialist
Someone could have installed the wrong refrigerant, or overcharged with R-134a. You would need a refrigerant gas detector to know.
It wasn't R-134a. Whatever it was, it weighed about about 2/3 as much as the specified amount of R-134a but had a [censored] more pressure and floated on top. It was probably just some helium or argon or some such that someone forgot about.
Okay.
Legally if an R-12 A/C system leaks, it must be filled with some kind of gas other than R-12, then a gas detector must be used to check every single part of the A/C system. Then when the repair is made, it is legal to pump that gas out and charge with R-12.
That is extremely rare, as most people prefer to just convert to R-134a if the A/C needs repair. The only time I ever hear of an R-12 system being recharged is either if someone has old cans, or if a restorer goes to extremes to make a car appear original.
Originally Posted By: artificialist
Someone could have installed the wrong refrigerant, or overcharged with R-134a. You would need a refrigerant gas detector to know.
It wasn't R-134a. Whatever it was, it weighed about about 2/3 as much as the specified amount of R-134a but had a [censored] more pressure and floated on top. It was probably just some helium or argon or some such that someone forgot about.
Okay.
Legally if an R-12 A/C system leaks, it must be filled with some kind of gas other than R-12, then a gas detector must be used to check every single part of the A/C system. Then when the repair is made, it is legal to pump that gas out and charge with R-12.
That is extremely rare, as most people prefer to just convert to R-134a if the A/C needs repair. The only time I ever hear of an R-12 system being recharged is either if someone has old cans, or if a restorer goes to extremes to make a car appear original.
Originally Posted By: yonyon
Is there a refrigerant that would have a static pressure in the neighborhood of 320 to 350 psi on a warm spring day?
it is the temperature of what the refrigerant is at in a container/system not necessarily the outside temperature. it can be 70°F outside but after you shut your car off the heat soak under the hood can make the refrigerant in your AC system that has never been turned on well over 100°F. so you need to take that into account when measuring pressure.
my guess is the system was run then shut off and pressure was measured shortly after. google temperature pressure charts for refrigerants, r134a @ 160° F is 300 psig.
it's true r410a has a high saturation temperature 300 psig @ 96°F, but i doubt it or any other refrigerant was put into the system, it would be too hard, too obvious, and it would also be mixed with r134a... assuming this is an r134a system.
the initial question posed is quite vague.
Is there a refrigerant that would have a static pressure in the neighborhood of 320 to 350 psi on a warm spring day?
it is the temperature of what the refrigerant is at in a container/system not necessarily the outside temperature. it can be 70°F outside but after you shut your car off the heat soak under the hood can make the refrigerant in your AC system that has never been turned on well over 100°F. so you need to take that into account when measuring pressure.
my guess is the system was run then shut off and pressure was measured shortly after. google temperature pressure charts for refrigerants, r134a @ 160° F is 300 psig.
it's true r410a has a high saturation temperature 300 psig @ 96°F, but i doubt it or any other refrigerant was put into the system, it would be too hard, too obvious, and it would also be mixed with r134a... assuming this is an r134a system.
the initial question posed is quite vague.
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