Air-Con advice needed...

[Husky_Dog]

I have a question regarding my air conditioning and climate control on my May 2005 Scenic 1.9 Dci…

I had my local Renault dealer here in Luxembourg check out the system one year ago as I felt the system had lost some of its efficiency. After having the car all day it appears all they did was to stick a temperature probe in to the vent and say yes it is within limits, and showed me a table of outside air temperature v vent temperature.

I pressed on for last summer feeling that the system only got cold on longer motor way trips where the mass flow of air over the condenser was greatest – in traffic around town I had the feeling that the fan blowing air in to the car was blowing warmer air in to the cabin. I don’t have one of these blue screens like on my old Clio which reflect some of the infra red away, so if I am in traffic facing in to the sun it aggravates the situation as the dash is getting hotter and hotter.

On Saturday I dropped in to a car service centre in France and had the system re-gassed at a cost of €59 (£40) which took just under one hour. After the service the pipe gets really cold leading in to the car. The pollen filter was replaced on the last service 5000 kms ago so is clean.

My question is why can’t I have really cold air blasting through the vents as well?

I generally have the system set in AUTO to about 19 – 20*C – but if I set 15*C (the coolest I can dial in) the air doesn’t really feel a lot cooler?

What am I missing on this system? Am I being unfair by comparing it to various hire cars that I drive through the year (Audi, Ford, in general)? On other makes I can have the temperature set to “North Pole” and have a constant blast of cold air coming through the vents at what ever speed or conditions I am driving in.

I run my system all the time in AUTO so the AC gets regular action. No leaks or problems were reported when it was re-gassed.

Is the only fix for me to go and buy another make of car? That would be a shame as I am very happy with the car, apart from feeling that something with the climate control is not quite right.

Anybody else feel the same about there Megs and Scenic?

[Ray]

try setting it on 15 degrees and manual... you'll notice the cold air then!
I do this when i'm really hot and after i've cooled down, i press the auto button.. seems to work.

I think it's just the body getting used to the temperatures

[Husky_Dog]

Thanks Ray.

I have done this in the past, but wanted to know if others had the same experience with their aircon.

Sound like you do...

Ray do you have the blue screen that reflect the Infra red?

I am thinking this could be part of my problem, as I have the standard screen. I was told by the dealer whan I purchased the car from new that these screens were no longer fitted - I think I should have pushed him a little harder!!

[Privilege]

My first Megane Privilege had the blue reflective windscreen, but my second Phase II didn't and I found the aircon/CC to be much more effective on the later car. I know they made some tweaks to the aircon, so maybe thats why.

[Husky_Dog]

My first Megane Privilege had the blue reflective windscreen, but my second Phase II didn't and I found the aircon/CC to be much more effective on the later car. I know they made some tweaks to the aircon, so maybe thats why.

Thats what the dealer told me too. Maybe he was telling the truth after all?

I would love to try all the manual mode as Ray suggested but I woke up this morning to find a 5' trench running the lenght of the road in front of my garage! but after all this is Luxembourg
I had to use the bus for work today...

Like you Privilege I found the air-con very cold in the begining, and had to dial it up to 21 or 22*C on a long run. Now it could be down on 15*C and not cool enough to warrent turning it up. That was why I questioned the system one year ago...

All I can say is that it is the figures that Renault use for the check of outside air temperature v vent temperature.

It must be my imagination then.

Would a blockage or any fault have been picked up when i had the system re-gassed or would it be a straight pressure check and re-gas and thats it?

[Husky_Dog]

Its done it again!!

Yesterday was very hot here in Luxembourg (indicated 29*C sunshine)

I was in traffic with the air-co set at 19.5*C and the cabin was no where near that cool, and all of a sudden I can feel warm, humid air blowing at me at the same time I can here "click - click" as the compressor is switching on and off - why did it stop in the first place?

After this I set 15*C but never felt the air was that cols whilst I was in the traffic.

Once I was moving again the air cooled down agin...

I ran it in the garage once I was home and its as if the high speed fan behind the engine radiator sometimes doesn't switch in to high speed when the car is in traffic, and the system just gives up and the compressor switches off. A couple of minutes later it switches back on, and some times the fan went in to really high speed to draw air over the radiator.

The air-con pipe never felt that cold when the car was in the garage, and never sweated like it does when I looked after a fast motor down the high-way.

Can anybody give me some troubleshooting advice here?

I am confussed as to weather everything is normal (although warm air in a traffic jam doesn't seem quite right to me)

Has anybody else experience of this behavior?

Thanks for help and advice in advance.

Will.

[DaveP]

I'm also having a/c issues. Mine is similar to yours Husky_dog, sometimes it blows nice and cold, other times barely even cool. One consistent thing seemed to be that if I went up a steep hill it would start to work and give a nice icy blast and then keep going. I thought that maybe the refrigerant was a bit low and maybe there is some kind of sensor that stops the compressor coming on when the refrigerant is below a certain level - most likely to be in the bottom of the system somewhere where its in liquid form as opposed to gas at the top. My theory being that when you go up a steep hill maybe some liquid runs back to the sensor and lets the compressor go (I could be talking nonsense - Ioften do!) At the last service I had it checked out and they claimed that there was no fault found but they eventaully agreed to check the refrigerant. It was weighed and found to be only 50g down but they topped it up to a full charge. It then worked absolutely fine for about a month but it has now gone back to only working when it feels like it. The steep hill trick is still working though! I'm thinking that maybe I'm right about the gas level and its leaking out again or maybe there is some other fault and I've just been lucky for the last month. Trouble with intermittent faults is they always work fine when you are at the dealers!

[Stranger]

Mine when bananas one time and I ended up having to have the whole lot replaced under warranty.

When I say bananas I mean really bananas the heater, cooler, fan and CC did / didn't work the temperature stayed at furnace hot, basically everything that you could think could possibly go wrong went wrong.

I too find with a lot of cars that setting the modes manually gives better results than using the auto and just dialling in a temperature.

[Husky_Dog]

Thanks for your input Dave P and Stranger.

I will try the hill trick Dave and let you know – there are quite a few hills in Luxembourg so I will try on my way home this evening.

On the high-way this afternoon (sunny and outside air temp indicated at 27*C) the system kept up nicely and I could just leave it at 19.5 – 20.5*C and not feel the system fluctuating.

My problem here is that as soon as I get in to town traffic, or stop strange thing go on – just like the aircon system is not man enough for the job (Even if I set manual and max cold)

As I said before the system was serviced and the gas weight check carried out 3 weeks ago.

It does get cold when motoring so not too worried about that side of things.

I am going to place a digital temp probe in to the centre vent and monitor what goes on. I will also try on a hill climb like Dave P suggested.

Keep an eye out for my findings…