hiya all.
Found that the air con in my Mk3.5 doesn’t seem that impressive. Had the pressure and gas levels checked and they were fine.
Any suggestions?
Cheers People.
Had mine re-gassed about a month ago and it’s much improved; great timing, too…
Hmm, normally it is impressively cool, especially if the gas is good.
Two things to consider,
- the air flow through the condenser might be compromised by road dirt, leaves, etc.
Inspect and clean if necessary.
- the air distribution to the cabin might not be working right.
Check the various flaps etc on the central air distribution are operating correctly. There might be a leaf or twig stuck in it. It can also be a bit of a pig to get to.
Look at the the various HVAC.pdf files on the Mellens site for details on how it works, most of the various NCs across the years are much the same, just with different software and sensors for climate control or basic.
You say that the gas pressure has been checked,but that doesn’t mean there is adequate freon in the system. A 10% reduction in gas charge quantity is enough to make a difference in performance,especially in this heat. The system needs to be drained,vacuumed and refilled with the correct charge weight.
As a relative newbie, I wasn’t too impressed with mine at first but then discovered that there’s a set of hood open options on the distribution dial so I set fan to auto, temp to min (15), and distribution to the hood open feet and face setting. It works fabulously to the point of frostbite.
I’m having similar problems with the air con on my 2008 NC Sport (RHT). It’s been checked for leaks and re-gassed so it should be OK. All the vents produce a good flow of air. If I turn the temperature up it will blow hot air. With the temperature dial set to 15 degrees and everything else set to auto, I can hear the air con kick in when I switch it on, but it just blows air at ambient temperature, which recently has been 30 degrees.
Are there any sensors in the cabin I can check easily?
There is a basic check you can do that does not need any special tools. Open the bonnet and locate the 2 aluminium a/con pipes that run into the bulkhead (pass side).Start engine,a/c switched on,let the engine idle for a few minutes. Feel the pipes with your hand .One pipe should be cold to the touch,the other should be warm.If this is the case ,then it is a reasonable to assume that the a/c function is working to some degree.If there is no variation of temp between the pipes,you have a problem.
Thanks. I’ll give that a try when I get home from work tomorrow.
One thing I did notice was that if I slowly turn the temperature dial up from 15 degrees the heater fan starts to slow down until I get to the ambient temperature it stops blowing air altogether. Then if I keep turning the temperature up on the dial it starts to blow warm air and the fan get faster again. I assume from this that the system is trying to cool the cabin as it should.
I’ll give those pipes a feel tomorrow and report back.
Thank you missfire. That was useful advice.
OK, I’ve had a chance to check the temperature of the two aluminium pipes. After 5 minutes with engine idling and air con turned on the pipes were both the same temperature, which was cool, but not really cold.
After checking the pipes, I rang my local garage who serviced and re-gassed the system for me a few months ago and they’ve offered to give the system a thorough check. They’re a reliable garage and I’m sure they’ll find the source of the problem. The system was working OK after it was serviced, so it’s either a slow leak that didn’t show up at the time, or something that’s gone wrong since. They mentioned injecting dye to check for leaks if necessary.
I’ve no idea when it stopped working because I rarely use the air con. I only drive the Mazda in dry weather and almost always drive with the roof down and air con switched off. It’s only in the recent heatwave that I’ve felt the need to switch on the air conditioning.
So many people dont , but with air con the short quote “use it or lose it” is one that must be followed.
^^^ I fully agree with the above statement, my daily driver always has the air-con set to auto, even in winter. I recently had the filter changed at 4 years old, it should have had it changed at 2 years old but it was missed. It was decent enough before the filter change but feels much more icy cold now.
A mate has just had his car in for the first MOT, he told them the air-con isn’t working very well, I’ve always told him to use it more but he seems reluctant thinking about fuel economy.
My Mk2 import with air con was lovely, top down in the kind of weather we have had recently and a cold blast of air in your face, pity the Mk3 I own now lacks it.
Is the clutch on the compressor kicking in? Or trying to and failing? Is there a wiring issue?
I’m sure you’ve already done this, and it is a silly question after all this time, but have you pressed the centre of the right hand dial to enable the air-con? The yellow LED under the letters AC should be lit.
Hi Richard FX. Yes, everything seems to be working except the air isn’t refrigerated. Compressor kicks in, switch lights come on, plenty of air being blown out of the vents (all modes). With the fan set to auto, it blows harder when the temperature dial is turned down and slows down again if I turn the temperature up.
The comments from Paul20v and MickAP are very interesting. My Volvo daily drive has it’s climate control on all the time, even when the sunroof is open. A Volvo mechanic once told me I should leave it on to keep the car properly ventilated, but I hadn’t realised it would be detrimental to the system if it isn’t used.
After reading various posts on this forum, I’m pretty much convinced it just needs re-gassing again. It may well be a case of “use it, or lose it”, or maybe a leak that wasn’t detected when the system was last serviced. I believe the standard leak test is to fill the system with an inert gas and check that it hasn’t lost pressure over a 30 minute period. This wouldn’t necessarily identify a minor leak. I’m sure my local garage will confirm if there are other, more serious problems.
Aircon used regularly helps keep the systems seals lubricated, hence they don’t lose there ability to do just that and you lose the refrigerant gas.
My Mazda’s air con is now re-gassed and working (for now at least) so I thought I’d post an update:
The system was checked out for me and no obvious leaks were found, but it was confirmed that a re-gas was needed. My local garage wanted £80 for a re-gas so I thought I’d shop around.
Firstly though, I decided to buy an air con test thermometer to provide me with some tangible data. These consist of a small dial on the end of a metal probe that you just slot into an air vent. Available for £8.81 from the world’s biggest online warehouse, but I found an almost identical one in a high street store for just £1.50 The only difference being the one I bought is sold as a BBQ thermometer and has a very nice picture of a cow on it. I tested it’s accuracy against a calibrated thermometer and found it to be amazingly accurate.
Using this thermometer, I established my Mazda’s air con was pumping out air that was around 2 degrees below ambient, and that cows need to be cooked at 70 degrees.
As for the re-gas, I decided to search on line using a website that provides quotes for any specified automotive job. Within an hour I received several quotes ranging from £30 to £80. The £30 quote was from a very well known chain of motoring accessory and bicycle stores / autocentres. It turns out though that the quoted price didn’t include materials (i.e. gas) and so the total price, including gas, would be £90.
The one I went with was from small chain of car service / MOT centres that has recently opened a new branch 3 miles from my home. Their quote for a re-gas was £45 including VAT which seemed like a really good deal (they normally charge £50).
So I booked it in to be done this morning. On the way there, the outside temp was 19 degrees and the air from the dash vents was 17 degrees. When driving home after the re-gas, the air from the vents was an icy cold 5 degrees.
I’ll keep the climate control on at all times in future, even in winter, so it doesn’t dry out again. I’ll also monitor the temperature over the next few days / weeks with my BBQ thermometer to check there are no slow leaks that weren’t found earlier. Hopefully everything is now OK. Bring on the heatwave!
Thanks again for all the useful advice.