1st Timer charging from cylinder

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Dave in Texas
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1st Timer charging from cylinder

Post by Dave in Texas »

I was given a partial cylinder DuPont R12(30lb tank). There wasn't much left in it so I thought I'd use as much as I could. Cylinder weighed 8.55lbs when I started and when it reached 5.96lbs there was no more liquid in tank. 60oz needed for full charge. Looks like I got 36oz in? Wasn't sure whether to keep compressor running or not, so I shut it down.
When there is no more liquid in a tank, what is the correct thing to do??
There is pressure in the tank but the compressor wasn't taking in any gas and weight on scale was not changing. Just unsure about dealing with empty tank...learning.
Thanks
Dave
Retired IBEW Electrician. Veteran ('61-'67)
1981 F100 (bought new) 300-6 4-sp stock truck(R12)
1987 Coupe Deville (R134a)
2003 Harley Low Rider
GM Tech
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Re: 1st Timer charging from cylinder

Post by GM Tech »

If tank has 80 psi and compressor is running and low side is 30 psi, then it will draw in refrigerant, turn tank upside down will help- warming tank will also help. when empty the tank should measure same as low side was when running...
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Dave in Texas
Posts: 25
Joined: Fri Jun 10, 2016 5:28 pm
Location: Austin Tx area

Re: 1st Timer charging from cylinder

Post by Dave in Texas »

GM Tech wrote:If tank has 80 psi and compressor is running and low side is 30 psi, then it will draw in refrigerant, turn tank upside down will help- warming tank will also help. when empty the tank should measure same as low side was when running...
Thank you for your response. Checked tank psi.....33psi. If my math is correct I still need to install 1lb+Xoz to get to full 60oz charge?
I appreciate your help.
Retired IBEW Electrician. Veteran ('61-'67)
1981 F100 (bought new) 300-6 4-sp stock truck(R12)
1987 Coupe Deville (R134a)
2003 Harley Low Rider
mk378
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Joined: Tue May 24, 2016 5:53 am

Re: 1st Timer charging from cylinder

Post by mk378 »

There's only a couple oz of gas left in that tank. You will need to procure more R-12. Empty tanks should be pulled into a vacuum using a recovery machine, then punch a hole in the tank and recycle the metal. The refrigerant in the recovery cylinder can be used.
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Dave in Texas
Posts: 25
Joined: Fri Jun 10, 2016 5:28 pm
Location: Austin Tx area

Re: 1st Timer charging from cylinder

Post by Dave in Texas »

mk378 wrote:There's only a couple oz of gas left in that tank. You will need to procure more R-12. Empty tanks should be pulled into a vacuum using a recovery machine, then punch a hole in the tank and recycle the metal. The refrigerant in the recovery cylinder can be used.
I will need to procure more R12....thanks
Retired IBEW Electrician. Veteran ('61-'67)
1981 F100 (bought new) 300-6 4-sp stock truck(R12)
1987 Coupe Deville (R134a)
2003 Harley Low Rider
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