ive heard that if you do not use the compressor it will starve of oil and lock up. my van hadn't had a charge in about five years and i decided to recharge it one day and the a/c blew supercold but the compressor was very very noisy. after three days of cool a/c in 100 degree weather the refrigerant leaked out and i didnt want to waste any more money on it so i never got to find out how long the compressor would have lasted. my guess not long. as i become a little more educated on a/c as i go i would probably replace the compressor anyway because if you take the time to properly repair the a/c and use the old compressor it might take a poop on you and blow all the "black death" all over your system making repairs previously made useless. on the other hand proper repair procedures might prevent the black death.

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1984 300SD Orient Red/ Palomino
1989 560SEC
2016 Mazda 6 6 speed manual
1995 Ford F-150 reg cab 4.9 5speed manual