Metal Air Con pipes.?

[woodways3]

I found the bigger of the two metal pipes going into the car has been leaking ,no gas in it now.I have a good used pipe.The slim pipe is Alloy . Question can the pipe be accessed from the cover at the bottom of the windscreen ,or is it what looks like a nightmare from within the car ??????? If so im wondering maybe to cut the old pipe insitue and join the better pipe with maybe a compression joint .Anyone done similar ?? I know where the old is leaking.

[VOLVOBOY]

Hi.
If i understand you correctly by removing the cover plate on the bulkhead you will see the Expansion Valve. Both large and small aircon pipes are connected to this by a holding plate and O-rings. Very simple to remove both pipes and worth changing the Expansion Valve at the same time.

[woodways3]

Originally Posted by VOLVOBOY

Hi.
If i understand you correctly by removing the cover plate on the bulkhead you will see the Expansion Valve. Both large and small aircon pipes are connected to this by a holding plate and O-rings. Very simple to remove both pipes and worth changing the Expansion Valve at the same time.

Thats great news,for a moment i thought the only access was from within the car.I guess the skuttle cover clips will all break upon removal?

[VOLVOBOY]

No , if you treat them like nuts and go carefull then they will spin off without breaking anything.

[woodways3]

[QUOTE=VOLVOBOY;2743042]No , if you treat them like nuts and go carefull the
n they will spin off without breaking anything.[/QUO

Hi i have no knowledge of the expansion valve ,does the two pipes fit into this unit? Is it easy to fit,and does it need any other gaskets ? Thanks for your help.

[VOLVOBOY]

Hi.
Expansion Valve is fixed by 2 cap head screws. A new part will come with new O-Rings. Two Rings seal under the valve against the Evaporator and two rings seat against your pipes. This job is simple but just a bit fiddly making sure not to drop anything.
There are two more O-Rings ( one on each pipe) that you need to inspect. They should be replaced usually but you can re-use if they are not deformed or hardened.
The main reason why these systems leak (apart from punctured condensers) is the ageing of the sealing rings so it makes sense to change what you can whilst you can.
As the system is open to air you should really replace the Receiver/Drier as a service item and put some lubricant in.
I don`t want to over blow any of this and put you off but the more you do now the better the system will be once you have it re-gassed. All the parts are simple bolt-on , bolt-off items.

[woodways3]

Originally Posted by VOLVOBOY

Hi.
Expansion Valve is fixed by 2 cap head screws. A new part will come with new O-Rings. Two Rings seal under the valve against the Evaporator and two rings seat against your pipes. This job is simple but just a bit fiddly making sure not to drop anything.
There are two more O-Rings ( one on each pipe) that you need to inspect. They should be replaced usually but you can re-use if they are not deformed or hardened.
The main reason why these systems leak (apart from punctured condensers) is the ageing of the sealing rings so it makes sense to change what you can whilst you can.
As the system is open to air you should really replace the Receiver/Drier as a service item and put some lubricant in.
I don`t want to over blow any of this and put you off but the more you do now the better the system will be once you have it re-gassed. All the parts are simple bolt-on , bolt-off items.

Very informative ,many thanks. Last question,is the drier receiver in the same area as the expansion valve ? Did you mean put oil inside this drier ? Sorry all new to me,air con.

[VOLVOBOY]

Hi again.
The Receiver/Drier is the small aluminium cylinder mounted next to the condenser on the offside. The best way to access it is to remove the front bumper and offside headlamp . This is more involved but really doesn`t take long to do. Plenty of good vids on you-tube.
The Drier has silica crystals inside that absorb any moisture in the A/C system. Moisture kills Compressors. The Drier has two pipes and a pressure sensor connected to the top. These parts are re-used on the new Drier and have O-Ring seals like the Expansion Valve.
The lubricant is PAG 46 oil and has a fluorescent dye. A replacement Drier would only need approx 30cc of oil which you can syringe inside. The trick is not to have the new Drier open to air for too long because the crystals will become saturated with moisture.- say no more than 30 mins in low humidity.
You could syringe a little extra PAG oil down the pipes you are replacing into the compressor - say 20cc to 30cc.

[woodways3]

Originally Posted by VOLVOBOY

Hi again.
The Receiver/Drier is the small aluminium cylinder mounted next to the condenser on the offside. The best way to access it is to remove the front bumper and offside headlamp . This is more involved but really doesn`t take long to do. Plenty of good vids on you-tube.
The Drier has silica crystals inside that absorb any moisture in the A/C system. Moisture kills Compressors. The Drier has two pipes and a pressure sensor connected to the top. These parts are re-used on the new Drier and have O-Ring seals like the Expansion Valve.
The lubricant is PAG 46 oil and has a fluorescent dye. A replacement Drier would only need approx 30cc of oil which you can syringe inside. The trick is not to have the new Drier open to air for too long because the crystals will become saturated with moisture.- say no more than 30 mins in low humidity.
You could syringe a little extra PAG oil down the pipes you are replacing into the compressor - say 20cc to 30cc.

Wow you really are an air con expert.Not sure if i can face doing that .especially as i have to do all the work outside .Im sure the bulkhead stuff will be taxing enough.But i understand the logik of doing all of the above.Many thanks.

[VOLVOBOY]

There. I knew it !!
I`ve talked you out of it.
The Drier is really more important than the Expansion Valve but if you don`t fancy it - fair enough. A good Air-con Co. will replace the Drier for you - at a cost of course.
When you take it to be re-gassed they must pressure test first and then vacuum down the system for at least 45 mins. Again you can ask them to put some lubricant in.
A good Co. will tell you how much Refrigerant has gone in. Volvo specify 1Kg . They will probably not get that amount in but should go as close as possible.