Air con - Ben
I've looked through the FAQ section of the site but would appreciate any additional advice.

When I switch my air con on a get a damp smell which eventually clears. Also if I switch it off while travelling, it tends to steam up the front windscreen and the air gets a warm a damp smell which takes quite a while to disperse! Is this normal? Will getting the aircon serviced/gas changed help, or is there something else I could do?
Re: Air con - Brian
It is due to condensation collecting in the system. The smell is bacteria/algae breeding in the moisture.
See a long previous thread for detailed information and advice.
Re: Air con - BrianT
I suspect you are getting condensation problems in the evaporator unit inside the dash. Any excessive condensation is supposed to drain out but if the hole is blocked it builds up, mould and slime grow and you get a bad smell. The fact you are getting fogging on the windscreen points to water in the interior of the ventilation system. These units need to be cleaned and sanitised on a regular basis, say every two years. Its a cost no one talks about when you buy the car, but as you have found, its a must.
Re: Air con - Dave N
You can get a Haynes manual for a/c principles, but it's not car specific.

On the mondeo, the condenser is in front of the rad, the evap is buried away in the heater box and can't easily be seen (or removed). It uses an orifice tube and low pressure switch rather than an expansion valve. The accumulator/drier is behind to n/s headlamp.
Re: Air con - Dave N
Brian T is correct. You can have it treated professionally (for a cost), or you can try yourslf with a spray from halfords or the like. An a/c service won't normally cover this unless you specifically ask.

Problem with DIY is getting close to the evaporator where the problem is, and some seem to be more fragrance than cleaner. A pro will have some stronger fluid and a special gun to get right in there. I would normally charge about a hours labour plus fluid. Ford specify what to do, and they'll charge you about £100.

The other thing to check is the evaporator drain. Let me know what car you have and I can steer you toward the drain pipe, as some are a bit obscure.
Re: Air con - Des G
An interesting discussion. I have just acquired a Ford Mondeo Ghia with air con, and after 35 years in the air con & refrig business, I am, of course, interested in the system. Advice from BrianT & Dave N is good, and it is clear that the average motor mechanic must have problems in dealing with the system. However guidance for the owner should be provided, and is non-existant in the manuals provided with the car - just to run the system for 30 mins once a month (no drying out suggested).

A year or two ago, in USA, there were reports similar to Ben's, plus evidence of spores being discharged and of people feeling ill - similar to the sick buildings 'syndrome' in UK in the 1980's.

I need to know where the air con components are - if only to watch over them eg for damage to the condenser which, I assume is with the radiator. A system diagram would also be useful. Does anyone know where these can be obtained? What do car manufacturers issue to trade repairers? Do Haynes manuals cover air con systems?
Re: Air con - Des G
Thanks Ben for your help. It gives me a start anyway - bonnet up in the morning to see what I can see. 1996 Mondeo diesel Haynes manual, I see, has aircon section. I'm looking for 2000 version manual, but I think it's not yet published. Regards, Des G.
Re: Air con - Des G
Sorry, Dave N: sent my thanks to Ben by mistake. Anyway, thanks to you! Des G.

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