Hello everybody. When the aircon is on full blast there is a "sooty" smell coming from the dashboard vents. I can't decide if it is present or not with aircon switched off. I have removed the dash panel and tried to clean inside the vents. Yes, there is a lot of Honk Kong pollution embedded on the inside of the vent pipes. Does anyone know where the air inlet is to the vent system when on both non and recirculating inputs (f & r). I want to inject a bacterial cleaner through the air ducts to see if this helps. (Masterace 4wd 2ltd 1990 auto) Thankyou

- (#3868) Ray Ambler, 18 Jul 02

Probably bugs in the system as you guess. Front intake is behind l/h headlamp, recirc behind the glovebox. Rear is recirc only, big grille on bulkhead near battery box. Remove it and defluff the evaporator while you're at it...

- (#3875) david miller, 18 Jul 02

Most likely to be to do with bacteria growth on the air con evaporators, this is caused by the fact that water condenses onto the evaporator of the air con as it cools the air (a bit like the steam from you bath condenses on the bathroom mirror) this is the water you see dripping out of the heater box on a humid day with air con running. However not all the water gets away & some sits on the evaporator, this then goes stale & bacteria grow on it, this introduces the nasty smells & in the extreme cases causes coughs & colds (now known as car flu) the only way to cure the problem is to kill the bacteria, there are several ways to do this, the most effective involves a garage using a machine that pumps a vapour around the heater/air con duct & through the evaporator to kill the bacteria, but you can get from motor factors an aerosol treatment that you can apply yourself by running the fan (Air con off) on recirculate & injecting the contents of the aerosol into the system to kill the bacteria. Air con manufacturers recommend this anti bacterial treatment is carried out every six months & full gas service is carried out every 2 years. Remember the Legionaires Disease scares from years ago, this was caused by exactly the smae problem with office & hotel air conditioning, so it just shows how ignoring the problem can be really nasty. Regards Rob.

- (#3878) Rob Drinkwater, 18 Jul 02

Thankyou to both Dave & Rob. I'll get on the case asap.

- (#3880) Ray Ambler, 18 Jul 02

Smells and allergy symptoms I'd be glad to get rid of. The local car valeting company referred me to a mobile car aircon specialist (Brake Engineering, Brighton) who is also in the Yellow pages. His advice
do it yourself with an aerosol from Halfords. Halfords - don't stock it any more. Nothing in other car shops either. Went back to Brake Engineering who promptly delivered a small (2.5oz, 71g) aerosol for £5. It's "Clean Air" from Green Island Inc USA. Says all the right things except what's actually in it (maybe that's why it isn't retailed here?).
Then it was take out the front lights - central unit, left (passenger side) sidelight, left indicator, left headlight, when you can see the fresh/recirculate flap above the left headlight position, and through it the front blower.
I was surprised at no sign of any filter to control pollen or even flies etc on the fresh air intake. Clean off all the road dirt and follow the instructions on the tin. The rear system is easier.
Car needs plenty of ventilation afterwards. One 71g aerosol is probably barely enough for our dual systems - and I don't have a cold box.
See Ace Answers entries on Bacterial Treatment.
Incidentally this aircon man says he refills with RS24 refrigerant to avoid the inflammable/butane options and too many mods to the system.

- (#3948) Dave Mason, 24 Jul 02

Following a previous posting I obtained a can of A/C deodouriser from a local A/C agent. Worked a treat, droped the can in the sort that out later pile. Yesterday noticed the lable coming off with something underneath. Cleaned it off and found the original maker who have this web site www.autodiamond.com do mail order and far cheaper including postage than I paid. Also have other products that may be of use.
Smelly aircon no more.

- (#5359) clive, 3 Sep 02

Nice one Clive!

I notice that they are currently promoting a general deodoriser/sanitiser called "La Bombe" at £11.99 on the front page of their website among the uses for which they include aircon ducts.

But I presume that you are talking about their DAE Air Conditioning Treatment, £10.99 for 400ml, which is on their "THE FULL RANGE" menu.

- (#5404) Dave Mason, 3 Sep 02

Yes the foam Air Conditioning Treatment (and I paid £16.99 for mine). Used the pipe from the Waxoyl kit to get as far up the ducts as possible. Ordered some last night and can expect delivery between 24 and 48 hours, so fast service too, shame I don't need it until next year.

- (#5405) clive, 4 Sep 02

Clive, you should anti bacterialise every six months or so, to prevent further build up of nasty bugs. Does the one you used just blow in through the output ducts, if so then it stands a good chance of being blown out by the fan & never hitting the evaporator (the cause of most of the problems) this is how the Wurth one works. The one I used comes from Wynns & goes into a machine called AIRCOMATIC, this uses ultrasonic waves to vapourise the liquid, you then point the pipe into the recirculate intake & leave it for 20 minutes or so, this then causes the vapour to go through the evaporator and kill off the bugs, as well as bugs inside the car as well, I did two treatments on the front air con & one on the rear, this cured the problem I had of always getting cold like symptoms when I used the air con. (often refered to as CAR FLU) This treatment is quite expensive though as you need the machine to use it (Garage Job) and most places charge around £30.00 for it to be done. Regards Rob.

- (#5406) Rob Drinkwater, 4 Sep 02

Rob,
The instruction is to run up the A/C, set the fan to low, stick the applicator pipe (the Waxoyl one was longer, but any bit of tubing will do), in as far as you can in main intake, and spray for 30 seconds. Turn fans off spray a burst in any other entry/exit point, again as deep as you can get it. Leave for 20 minutes or so then fire up on low speed if nothing flies out try faster speeds, if it does leave it for another ten minutes and repeat.
The foam coats, kills and protects for at least 6 months so it will be next year before I need reapply. The down side is you can not tell if you cover all that needs to be covered. However as I have not had the A/C serviced yet I would get it all done professionaly if there are no problems with the MOT in Feb.

- (#5407) clive, 4 Sep 02

Can arrived, different name and instructions (similar but not the same), bigger 440ml size, still with waste of time applicator. Last line of instructions along the lines " ensure car is well aired before returning to your customer" so assume it is aimed at garage use.

- (#5425) clive, 6 Sep 02