Couple a/c questions.

[ACoyle]

1) How much refrigerant is a full charge?
2) Wouod it be possible that a 2004 that has not been serviced would be flat empty?

A 1# can brought it up to 35#/sqin.

I'm assuming more is wrong. Hoping for the best.

Andy

 

[B.G. Smith]

There is usually a deal near the radiator that tells refrigerant type and amount. 32ounces I think. If the AC has been idle and has a leak, yes it can be zero.


















truck has

 

[Blu-meanie]

I just played the A/C woes game. Took it to the dealer, paid $160 for my trouble and was told there was no leak and gave me a part number for their best guess and a quote to do the job...$604. I went home and was looking around and found a leak at the low schrader valve. Made a tool and tightened the valve. I bought all the gauges, vacuum pump, etc for around $300 including the part. When I tried to evac the system, there wasn't much freon left. Yesterday I replaced the line, serviced the system with 1 oz of compressor oil (as per the manual) and 30 oz of R134A. Worked fine, so we'll see.

 

[Tuesdak]

Unlike GM systems "our" AC systems can run in a vacuum as there is only a temp sensor on the low side: no pressure switch. Thus the system can run in a vacuum on the low side and air/moisture can leak into the system. This means with a low to no charge you need to pull a vacuum on the system to recharge it. As the accumulator removes moisture it's best to replace it as well.

So pull a vacuum to make sure there are no major leaks, replace accumulator, pull vacuum again, then charge by weight. I recall my 2003 was 34oz that is 2oz shy of 2 LB. Label under the hood with this amount.

Automotive systems slowly leak, period. The compressor shaft seal is a very slow leak to keep it lubed. The rubber hoses also slowly leak. Nothing you can detect with a sniffer or it's a real problem. Our older systems also blow the high pressure relief valve and dump 1/2 the charge under some conditions where the fan can't kick in fast enough on a cold start.

 

[B.G. Smith]

Sorry but our systems don't run under vacuum, there is a clutch cycling switch which opens around 26# and cuts the compressor off.

 

[Tuesdak]

Dodge add the low pressure switch after 2003 MY?

 

[ACoyle]

Thank you all. I'm on it.