Air conditioning not working - help !!

[v70tom]

Sorry, I guess this question come up many times but I can't find any post for my problem.

On my v70
1998 v70 fwd 170 bhp non turbo
Is the problem the aircon does not work.
The light on the dash button comes on when it switch on,
The blower is working but just the normal outside temp air comes in.

Today I was in a garage to check the aircon and the guy ( not aircon trained ) said the clutch on the unit is not coming on when
Pressing the button.
I said it has something to do with the nit.
Fuse
Cable
Etc.

Anyone encounterd the same problem and has some advise for me to start looking on the right place.
I don't really want to go to a garage which is doing airconditionings and paying out for what I may check myself.
Also if I be able to fix it myself i don't mind doing it.

I just don't want to buy a unit and dismantle the engine at to exchange it.
If the unit is broke by defently I just forget about the aircon instead spending a lot penny's in it.

If its only a wire or fuse or something easy I do it, no question, but where to start.
Thanks

[stephenevans99]

First thing is to have an AC guy check how much refrigerant is in it.....if it's empty or even just low, the clutch on the compressor won't engage.

It may just need servicing/refilling. Your car requires 750 - 825 grams of refrigerant.

[M-R-P]

Take it to an aircon specialist that does a "cold or your money back" guarantee. You'll either pay for a regass and get working a/c or they'll tell you exactly what's wrong with it for free.

[viggen]

Hi I took my car to three so called specialists in the end I used a guy in bham
He changed two pressure switches regas and never looked back
My car 1998 c70. get it regassed with die to spot any leaks.
They can measure how much gas is currently in the system
He recommends every three years service required but aircon probs can be expensive

[stephenevans99]

Whilst on the subject of AC.....if anyone needs a pdf of refrigerant quantities for ALL makes and models - pm me and I can email it.

Here's the Volvo page....

http://i24.photobucket.com/albums/c2/stephenevans99/screen-capture-3.jpg (http://s24.photobucket.com/user/stephenevans99/media/screen-capture-3.jpg.html)

[AndysR]

You can quickly tell if it's a gas or pressure switch issue by switching the system on removing the pressure switch multiplug and bridging the plug. As soon as you do this you should hear the clutch on the compressor click in and the compressor will engage. Do this for only a split second though because if your system is low/out of gas it will also be out of lubricant for the compressor and it will kill the compressor. Naturally the engine needs to also be running when you do this. If the compressor cuts in I would go and get the system gas levels checked/adjusted first. If that doesn't cure it you need a pressure switch. If the compressor doesn't even engage by bridging the pressure switch then either the compressor is faulty or you have a wiring or system fault.

[nobananas]

If the system is in good condition and the pressure is okay you may well have a weak clutch. My 850 was like this a few years back, when the air con was on the clutch wouldn't pull in although it was getting power as was shown by using a test light on the clutch feed. If I gave the clutch a direct live off the battery it would kick in. The reason for this was because there is quite a current drop through the original wiring and because the clutch was a bit weak there wasn't enough current to pull it in but straight to the battery there was plenty. I wired in a simple switching relay that was closed by the original clutch feed that then fed the clutch directly off the battery through an inline fuse which solved the problem.

[Blackdog]

Have you changed the cabin pollen filter?

[v70tom]

Cabin pollen filter?
No, surely the compressor unit still would engage?

Ad thanks so far for the help guys - I look for a guy which is doing this rehash no work no fee thingi.

In the meanwhile untill I find someone I try the option with direct to batterie.

The green light on the switch apparently should flash when the unit has a fault? But it is on as it would be working. Hmmmmm?

[nobananas]

This is correct, if there is a fault that the system can detect the AC light will flash for a short while when the vehicle is first started.