Using a set of a/c gauges put the blue hose on the low side (suction side) and the red hose on the high side (discharge side) and make sure that there is no freon in the system and if you have freon in the system then you will have to go to an automotive a/c shop and have them reclaim it for you..
Put the yellow hose on your vacuum pump and let it run for about 1 hour and then let it sit for 1 hour so that you can see if it will at least hold the vacuum pulled.
If so then let it run for an additional hour and then start the recharging process remembering to keep the low side readings between 30 to 40psi and the high side between 200 to 250psi depending on the outside temperature…………….
You will not be able to charge the system correctly plus you will have moisture stuck in the system.....
If the system is being completely filled, a vacuum will have to be pulled on the system. If the system just needs to be topped off then a vacuum pull is not needed.
Pulling a vacuum on an ac system requires a vacuum pump or venturi pump with the correct type connector. The pump is connected to the low side ac port, and the vacuum could take an hour to pull depending on the pump size.
Between 28 to 30..........
run motor and set A/C on max, blower on full, pull a vacuum on the system and recharge with R12a 2.9Lbs
Remove the freon from the system with a reclaiming machine. With the system empty, disconnect the lines from the condenser and bolt in the new one. use new o rings as well. Pull an entire system vacuum, then refill the AC unit with freon.
To test for leakage in the system.
Sterilant
Moisture in a vehicles AC system can react with the R134a or R12 refrigerant and create an acid that will eventually eat through seals and o-rings and even orifice tube parts. It is recommended you vacuum your system whenever it loses charge or whenever your extremely low on refrigerant. You can rent a vacuum at Auto Zone for free (200$ refundable deposit) and pull a 26-28 inch vacuum.
Remove the freon from the system. Remove the ac compressor belt and disconnect the lines. Unbolt the compressor, remove it, then bolt the new one in place. Reconnect the lines and belt. Pull a vacuum on the system then refill with freon.
Which vacuum diagram The Underhood for the engine or the vacuum for the interior /AC system?
Remove the freon from the ac system and release the pressure on the 2001 Dodge. Loosen the fittings on the dryer and remove it. Install a new drier, and new o rings. Pull a vacuum on the system then fill with new freon.