Aircon Not Working / Hissing From Glove Box

[shepheap]

I've been reading all the old posts but still finding it difficult to come up with one that fits my particular problem:

 

Over the last week or two I have noticed hissing noise from the glove box area of the dash. Today I had the glove box out and started to dismantle the dash to try and locate what I assumed to be a leak, however due to it being a warm day I thought I woudl try the aircon only to find that it was not working.

 

I also noted that if the climate control was set to Econ the noise went away so preumably the hissing is linked to the aircon problem.

I have read a post that refers to low pressure in the system possibly causing hissing noises in the area of the glove box, but I checked the aircon low pressure with a Halfords refill and this showed that it was OK and it occasionally fluctuated which I assume indicates that the compressor is probably working as well(?)

 

If I switch the climate to Auto and turn the temp down to 18deg c there till appears to be some warm air coming through the vents (only slight) with the hissing in the background.

 

I'm not sure whether to go to my local garage which has full aircon evac and refill capabilities (and pressure testing) and just get it tested nd refilled, or whether I should be looking for another fault first.

 

Any suggestiions gratefully received.

[Bigjeeze]

I seem to remember posters here saying that when the hissing sound emanates from the glovebox the evaoporator is shot. I would go for the refill/test so that you know one way or the other what is wrong.

[shepheap]

I seem to remember posters here saying that when the hissing sound emanates from the glovebox the evaoporator is shot. I would go for the refill/test so that you know one way or the other what is wrong.

Thanks. The evaporator is likely to be a tarting point once the pressure/fill has been checked.

 

Any other ideas from anyone before it goes in on Tuesday?

[shepheap]

Update - Still not wking! :16:

Went into the garage on Tuesday. When they connected up there was no gas in the system so they filled it and chcked for leaks but could not find any.

The system worked for a short time with the temp at vents being 1deg c, but after a couple of minutes it stopped and the temperature increased. The gas was still in the system and no apparent leakage but it hadn't been in for long enough to see if there was slow leakage.

Their suggestion at the moment is that it could be the dryer as that has a filter in it which could be blocked and needs replacing.

Any suggestions?

 

The gas has now been vacuumed out in case their is a leak pending my thoughts on what to do next.

 

Help please!!!!

[Steven.Langdale]

Update - Still not wking! :blink:

Went into the garage on Tuesday. When they connected up there was no gas in the system so they filled it and chcked for leaks but could not find any.

The system worked for a short time with the temp at vents being 1deg c, but after a couple of minutes it stopped and the temperature increased. The gas was still in the system and no apparent leakage but it hadn't been in for long enough to see if there was slow leakage.

Their suggestion at the moment is that it could be the dryer as that has a filter in it which could be blocked and needs replacing.

Any suggestions?

 

The gas has now been vacuumed out in case their is a leak pending my thoughts on what to do next.

 

Help please!!!!

 

In my experience, the hissing sound is actually comming from the Pressure valve on the bulkhead of the engine bay, but as it's "behind" the glove box, thats where you'll hear it. If it was this, thats a VERY good indication that you were low on refrigerant. you're basically not getting enough pressure to get the refrigerant liquid on the high pressure side of the valve. So you did the right thing getting it re-gassed.

 

It could be the reciever/dryer, how old is the car? when did the aircon last work?

 

After it stopped, did the compressor clutch dissengage and not re-engage? How long did you leave it running before giving up?

 

I think the commonest place for these things to leak is the high pressure aluminium pipe from the reciever dryer to the pressure valve, right where the clamp is. I'm assuming they checked there? If not take a look yourself, if it's oily, then it's probably leaking. from the front for the car its on the left hand side running from the very front to the back of the engine bay. It's about 7-8mm diameter, with one clamp bolted to the frame.

 

Steven

[shepheap]

Update - Still not wking! :blink:

Went into the garage on Tuesday. When they connected up there was no gas in the system so they filled it and chcked for leaks but could not find any.

The system worked for a short time with the temp at vents being 1deg c, but after a couple of minutes it stopped and the temperature increased. The gas was still in the system and no apparent leakage but it hadn't been in for long enough to see if there was slow leakage.

Their suggestion at the moment is that it could be the dryer as that has a filter in it which could be blocked and needs replacing.

Any suggestions?

 

The gas has now been vacuumed out in case their is a leak pending my thoughts on what to do next.

 

Help please!!!!

 

In my experience, the hissing sound is actually comming from the Pressure valve on the bulkhead of the engine bay, but as it's "behind" the glove box, thats where you'll hear it. If it was this, thats a VERY good indication that you were low on refrigerant. you're basically not getting enough pressure to get the refrigerant liquid on the high pressure side of the valve. So you did the right thing getting it re-gassed.

 

It could be the reciever/dryer, how old is the car? when did the aircon last work?

 

After it stopped, did the compressor clutch dissengage and not re-engage? How long did you leave it running before giving up?

 

I think the commonest place for these things to leak is the high pressure aluminium pipe from the reciever dryer to the pressure valve, right where the clamp is. I'm assuming they checked there? If not take a look yourself, if it's oily, then it's probably leaking. from the front for the car its on the left hand side running from the very front to the back of the engine bay. It's about 7-8mm diameter, with one clamp bolted to the frame.

 

Steven

 

Steven - Thanks for your reply;

 

The car is a 2003 TDi, the air con last worked a few weeks before I started to get it checked out (climate control so on most of the time).

 

After the re-gas the clutch was engaging and there was briefly some cooler (but not cold) air coming through, so I decided to leave it on Econ whilst trying to identify the fault. This has now been made easier as a couple of days ago I moved the car and found a puddle of green dye on the floor!

 

I haven't had a close look yet but it has come out where the front off side inner wing meets the engine tray which sounds as though coincides with the pipe you describe, and also (having done some more research on line last night) roughly where the receiver/dryer is located which is known to have leak problems found here

 

Hopefully have time to get underneath the car and chase the leak today.

[shepheap]

Update - Still not wking! :blink:

Went into the garage on Tuesday. When they connected up there was no gas in the system so they filled it and chcked for leaks but could not find any.

The system worked for a short time with the temp at vents being 1deg c, but after a couple of minutes it stopped and the temperature increased. The gas was still in the system and no apparent leakage but it hadn't been in for long enough to see if there was slow leakage.

Their suggestion at the moment is that it could be the dryer as that has a filter in it which could be blocked and needs replacing.

Any suggestions?

 

The gas has now been vacuumed out in case their is a leak pending my thoughts on what to do next.

 

Help please!!!!

 

In my experience, the hissing sound is actually comming from the Pressure valve on the bulkhead of the engine bay, but as it's "behind" the glove box, thats where you'll hear it. If it was this, thats a VERY good indication that you were low on refrigerant. you're basically not getting enough pressure to get the refrigerant liquid on the high pressure side of the valve. So you did the right thing getting it re-gassed.

 

It could be the reciever/dryer, how old is the car? when did the aircon last work?

 

After it stopped, did the compressor clutch dissengage and not re-engage? How long did you leave it running before giving up?

 

I think the commonest place for these things to leak is the high pressure aluminium pipe from the reciever dryer to the pressure valve, right where the clamp is. I'm assuming they checked there? If not take a look yourself, if it's oily, then it's probably leaking. from the front for the car its on the left hand side running from the very front to the back of the engine bay. It's about 7-8mm diameter, with one clamp bolted to the frame.

 

Steven

[Steven.Langdale]

Steven - Thanks for your reply;

 

The car is a 2003 TDi, the air con last worked a few weeks before I started to get it checked out (climate control so on most of the time).

 

After the re-gas the clutch was engaging and there was briefly some cooler (but not cold) air coming through, so I decided to leave it on Econ whilst trying to identify the fault. This has now been made easier as a couple of days ago I moved the car and found a puddle of green dye on the floor!

 

I haven't had a close look yet but it has come out where the front off side inner wing meets the engine tray which sounds as though coincides with the pipe you describe, and also (having done some more research on line last night) roughly where the receiver/dryer is located which is known to have leak problems found here

 

Hopefully have time to get underneath the car and chase the leak today.

 

 

If you get under the car and look at the reciever dryer, right behind the bumper. The small pipe running back will be the one.

 

I see your in Peterborough, I cant say I've had a huge amount of sucsess with the local big dealer there :blink:

 

The pipe is not too bad to swap yourself, the undertray will need to come off.

 

I did one last week, the pipe and 4 new O rings (you need to take off both from the pressure valve & receiver/dryer) was approx