Recharging AC pressure on low pressure port question

My AC is not working and I have a couple of questions about testing refrigerant levels. Does the compressor have to be engaged to test the pressure on the low port. I bought a bottle of refrigerant that has a gauge attached. Without starting the car I attached the can to the low port and the reading went up to about 50. I then started the car and tuned the ac on max the reading was about about 40 . The problem is, I am not sure that the compressor is engaging. Would the compressor have to engage for me to get an accurate reading of whether there is enough Freon in the system.? Also, the Ac fan use to come on whenever I turned on the AC and now it does not. Could this have something to do with my AC not working?

Check both your AC fuse + relay.

Yes, the only fuse I could see was a 10 amp fuse in the fuse box and I replaced it. As for the relay, how do you remove it. Do you take a flat head screw driver and pry the relay out?

What year Venture?

A/C compressor must be running for proper death kit reading.

Your compressor will engage at 47 or above static pressure (engine off).

Your cooling fans will come on once a/c generates 175psi discharge pressure-- evidently yours is not capable of that-- and is most likely low on refrigerant.

65% of a/c failures are due to loss of refrigerant-- tell me your model year and I will tell you top areas to look for your leak........

1998 Chevy Venture LS 225,000 miles - I purchased the van at 102,000 miles

What is a death kit?

Fuse's + relays are just plug play.
Roll with another the same type.

Caution - You don't want to connect a can of 134a to the high pressure side, the low pressure side should have the same fittiing as your kit.

A '98 U-van top leak location is compressor shaft seal, next is compressor belly, then 3rd- take a good look at rear 3/8" liquid line right above gas tank filler tube, and under black plastic insulation- look for oily residue---I've spliced about a dozen '97-02 U-vans there.

1998 Chevy Venture LS 225,000 miles - I purchased the van at 102,000 miles

What is a death kit?

Death kits are the things like what you by at wallmart.
One hose one gauge one can with sealer and sometimes with a propane/butane mix than can blow your hand /head off and van up and then burn you up.

Whe checking or charging a AC system never just use on gauge.
Always use a AC gauge SET with a high and low side gauge and never let high side get over the 350-400 lb range.
A problem ac system or a overcharge and you high side pressuere can go over 400-500 lbs and blow sky high.
Also with a propane/butane mixer like a LOT OF DEATH KITS HAVE AFTER IT BLOWS THEN IT MAY BURN.

This one shows one blowing up and almost killing the dude.

http://www.youtube.com/watch?v=DjtowzVzl_4




http://www.imcool.com/articles/aircondition/Porsche_928_Refrigerant_Fire.htm

http://www.autoacforum.com/messageview.cfm?catid=2&threadid=17027&FTVAR_MSGDBTABLE=


http://www.youtube.com/watch?v=DjtowzVzl_4


http://www.vasa.org.au/images/movies/hc_demo.mov