Re-assembling Factory AC System

[Brabham]

Hi guys,

            I am about to commence the re-installation of some of my factory air-con system. I have the receiver-drier but it has been sitting open to the atmosphere for a few years. Can I still use it or do I need a new one? Also I was told that if I re-use it that this may damage the compressor due to moisture entering it. Is there any truth to this or should I re-use it?

 

Cheers. 

[KatoKid]

Deffinitly dont use it.

 

Would be adviseable to check with whoever you are going to get to vac and charge the system as compressor and seals need to be compatible with R134a gas and PAG oils.

[Linton]

Deffinitly dont use it.

 

Would be adviseable to check with whoever you are going to get to vac and charge the system as compressor and seals need to be compatible with R134a gas and PAG oils.

+1

[Wayne G]

Don't use it because if it has been exposed to air for that time it will have absorbed it's fill of moisture. 

 

Before getting too involved, talk to an ac tech and find out what seals and hoses need to be replaced.  You may find that going to 134a may require a larger condenser but ask an expert, which I am not.

[Brabham]

Cheers. Are new ones available from Nissan? I was going to use something called Hi-Chill which apparently means that you do not have to change seals and rebuild compressor etc, just gas and go.

[Riceburner]

The biggest enemy is dirt/dust, if a triple evacuation is done the all moisture present will boil of when the vac is broken with nitrogen. Its definately worth getting a new one, I hate to see you fit it only to find it has a partial or full blockage. Have all the parts been sealed up with caps or tape?

[Brabham]

Unfortunately all the parts and hoses have been left open to atmosphere. All the AC setup in the engine bay was disassembled by PO and stuck in the back of the car. He also managed to lose some of the bits . Will do my best to clean out the hoses as much as I can.

 

How does the receiver/dryer work - what media does it use to remove moisture?

 

What is meant by triple evacuation? So if done properly and I cannot find a replacement then the receiver/dryer may be salvageble? Is there any truth that moisture in the lines will kill the compressor?

 

Cheers.

[Wayne G]

The drier is a serviceable part, replaced as a unit so there will be something available. I think the inside has something similar to those silica beads that come with the endless supply of new shoes my wife gets, but don't quote me. 

[Riceburner]

If there's moisture in the system in can break valve plates in the compressor, the moisture can also freeze causing blockages, especially in the t.x valve or orifice. Triple evacuation is when the system is vacced out 3times, each time the vacuum is broken with nitrogen. When the vac is pulled the moisture freezes, then when it's broken with nitrogen the pressure and temperature changes dramatically and this 'boils' off the moisture. This is done 3times.

 

I would get a new dryer, flexible suction/discharge lines and try cleaning blowing everything out with nitrogen.

[matty260z]

As everyone has said definately replace the drier.

 

You shouldn't need to replace the hoses but could be a good option if they've been sitting around for a while, I can definately recommed a few places that can make new hoses etc for you. After everything is back together ask your local A/C mob to flush the system severval times before gassing. And DON'T use that Hi-Chill gas stick to R134A, which will become obsolete with a year or 2 anyway, being replaced with HF1234YF.

 

If you need help chasing parts PM me.