How much more freon will a system take when vacuumed vs. empty?

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atikovi
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How much more freon will a system take when vacuumed vs. empty?

Post by atikovi »

This is just a beater that isn't driven much. Evac and charged a month ago and got ice cold air for a week. Haven't used the a/c in 2 weeks but now it doesn't work and the gauges barely show pressure. Not worth finding and fixing the problem when I can recharge for $3 of freon a few times during the summer. Instead of evacuating before charging I was going to just charge it with a few ounces less freon than the capacity on the sticker. Just wanted to know how much less when the pressure is near 5 or 10 psi to start with?
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Cusser
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Re: How much more freon will a system take when vacuumed vs. empty?

Post by Cusser »

atikovi wrote:Not worth finding and fixing the problem when I can recharge for $3 of freon a few times during the summer.
This is contrary to federal environmental regulations, leak needs to be fixed.
atikovi
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Re: How much more freon will a system take when vacuumed vs. empty?

Post by atikovi »

Cusser wrote:This is contrary to federal environmental regulations, leak needs to be fixed.
Can you link to the regulation? What I see is https://macsworldwide.wordpress.com/201 ... -recharge/ saying,

The U.S. Environmental Protection Agency (EPA) regulates mobile A/C system service, basically by requiring technicians to become Section 609 Certified and to use equipment and methods that meet certain standards. But one thing it doesn’t require is leak repair, which may seem counterintuitive for the nation’s top environmental agency.

Are there newer regs that supersede this?
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bohica2xo
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Re: How much more freon will a system take when vacuumed vs. empty?

Post by bohica2xo »

MACS is not the EPA. Adding refrigerant to a system you KNOW has a huge leak is KNOWINGLY and WILLFULLY releasing refrigerant.
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cool2bcool
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Re: How much more freon will a system take when vacuumed vs. empty?

Post by cool2bcool »

Legalities aside, when the a/c is loosing that much refrigerant you need to fix the leak. Its probably leaking oil out too and the system will never work as well as it could without the proper vacuum pulled and amount of refrigerant added. It will cost you more money in the long run doing it like you are because eventually you will probably blow up the compressor and have to replace that, the drier and the condenser at min. In fact a leak that fast you would easily be able to find even with soapy water. If the system is almost empty anyway whats the difference in taking it apart, replacing the broken part putting it together and recharging? Its literally only going to cost you some time and the replacement part assuming you have the tools and knowledge. You are going to be using dam near the same amount of refrigerant to recharge. Plus you don't have to keep messing with it by topping it off using money and time.

If you had a tire leak, would you just keep refilling the tire, or would you plug/patch it and be done with it. Simply makes no sense not to repair it.
atikovi
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Re: How much more freon will a system take when vacuumed vs. empty?

Post by atikovi »

I understand but a tire patch is $2. Pretty sure this is a hose leaking where it's been rubbing against the frame and that's $200. But because the bolt that attaches it to the evaporator usually snaps off, I'd probably have to replace that. Not worth it to me on a cheap car. If the compressor blows I'll go without a/c.
billr
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Re: How much more freon will a system take when vacuumed vs. empty?

Post by billr »

When the system is low, and you can't go by weight added, use the high/low gauges. Does that answer your actual question?
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