Originally Posted by leathermang

No, it would not have to be fully charged....
but it would need more than you would want to install just to check the system...and risk losing the refrigerant..
For a quick test you can direct wire the compressor to the battery...
a few seconds will not hurt it..
but do make sure you have checked the oil level in the York... it has a sump unlike our R-4's... You have to make a little dipstick to check it...

You should fully describe the situation you are dealing with to get the most and safest help on the forum.... how long not working... what do you know about it.... etc..

And describe your AC education level....and the tools you own , etc...