Water Leak - Please Confirm It's Just The Air Con!? :-)

[BeechCustom]

Hey all

I had a leak on my 4.2 2000 vvti Rav4 the other week. It was coming from the black square box looking thing that is central and just behind the front suspention system (obviously looking underneath the car). A little pool of water had been formed and when I checked it there was no evidence of coolant - it was just pure water. A friend of mine said that it's just waste from the air con system. I'd been getting stressed driving around London and had got the air con on full prior to noticing the leak. I'd not used the air con for ages.

So - can anyone confirm that the leaking is just waste from the air con and nothing to be concerned about? I've got a trip to Scotland coming up soon so I want to be sure the car isnt gonna let me down on a 1000 mile trip!

Many thanks.

[Davrav]

Can't confirm but sounds like it. Have you tried using the aircon since? If so, did you notice similar puddle appear when parked?

[BeechCustom]

I noticed that there were a few drops a day or so after I'd used the aircon which made me slightly concerned but I haven't noticed anything since. I'll use the aircon on a return journey today and check for leaking afterwards.

[igormus]

hi matey

do not say a waste -- cos the waste is those valued but lost .The water in question is normal condensate from an evaporator -- just be sure this pool is under the A/C drain tube (dia 12-15 mm) under the car.Besides -- check with coolant expansion tank.regards / Igor

[IanXT4]

When my AC is on I normally have a puddle under the car after its stopped for a while. The more humid the weather the more water gets removed by the AC and the larger the puddle.

The location of your puddle sounds right and if you had not noticed its pretty humid at the moment

I find its always a good idea to mark the level of your coolant bottle when its cold. Then check it from time to time (when cold) it will vary very slightly with changes in ambient temperature and probably loose a very slight amount to evaporation over time. However any sudden dramatic changes will highlight a problem.

[igormus]

I noticed that there were a few drops a day or so after I'd used the aircon which made me slightly concerned but I haven't noticed anything since.

Few drops --- I would inspect origination.

Normally A/C gives more drops subject to: the mosture in the air is big, let say in hot spring or summer or before the rain.

Normally small drops quantity is a signall of either dry air in winter or small freon gas pressure or other drops origination, such us coolant leak

regards / Igor

I'll use the aircon on a return journey today and check for leaking afterwards.

[firemac]

I noticed that there were a few drops a day or so after I'd used the aircon which made me slightly concerned but I haven't noticed anything since. I'll use the aircon on a return journey today and check for leaking afterwards.

If you're using the aircon regularly, you should get a little puddle of water just under the rearmost area of the engine after you switch off. As long as it is plain water, i.e. not coloured with coolant, for example, it is only surface water dripping off the aircon condenser and is normal.

For what it's worth, you need to run the aircon regularly (I believe once a month at least) to make sure that the seals in the system are lubricated and don't harden & fail thereby causing a loss of coolant. I appreciate that the aircon does impact MPG to some extent but I keep it on all the time as it keeps the cabin fresh & eliminates condensation, particularly important in the colder months. I also run a can of aircon sanitiser (Comma or similar) through the system once a year to help prevent the build up of fungus which can cause all sorts of problems over time - mind you, if the system is on all the time, this is not really necessary & is really belt & braces.

[Big Kev]

Not tae worry....it's so wet up here that (a) you won't see the wee puddle on the ground, and (B) you won't be using your air con much in oor weather......

Cheery Kev

[BeechCustom]

I had the aircon on full today. I checked the car before leaving and it wasn't dripping anything. I travelled about 10 miles then parked up and sure enough the water was clearly dripping from the same place as before. This would have been around 4pm. It was around 19deg c and pretty humid. I travelled a further 10 miles to the next client and parked up and once again saw drops of water but not as much as previously. I travelled home around 20 miles and by this time the outside temp has dropped. I just checked for leaks after parking up and there is a very small puddle on the garage floor. I checked coolant levels a for a few days after I first noticed the 'leak' and there was no evidence of loosing coolant.

[igormus]

yes it is definitely condensate from evaporator.

ok then nothing to worry about

it would be worse if nothing was dropped at this humidity.

regards / Igor

[Kenan Yigiter]

(I know this thread is old, but I just found it when searching)

For some people in this thread that are saying the condensation is coming from the evaporator.  As far as I know, that does not happen the evaporator.   Condensation in modern vehicle AC systems comes from the Condenser, which is located at the front of the vehicle (kind of looks like a radiator).  The evaporator that you guys are mentioning is located inside the car in the passenger compartment.  

When the Compressor that is connected to the crankshaft via a drive belt runs, looks like a small motor, the compressor pumps the gaseous form of the refrigerant (that's the liquid/gas that is flowing around the AC system),  to the Compressor.    

When the refrigerant moves from the Compressor to the Condenser, the Compressor has compress the refrigerant, causing the pressure to increase and the temperature of the refrigerant to increase which causes the refrigerant to turn into gas form.   When the gas enters the top of the Condenser, it is hot at around 85 degC with high pressure, when it goes down the condenser, the temperature drops with the pressure constant, turning it from gas to liquid form.   From Science, rapid cooling causes condensation (those water droplets).  

Then later it goes to the Evaporator, Receiver, Expansion valve.

From what I can tell, those water droplets comes from the condensation from the Condenser, but other websites are still saying Evaporator, I'm not sure why.

Regards, Kenan

[Kenan Yigiter]

Ohhh yeah, I should also mention.  Yeah it is normal, no need to worry.  Condensation water droplets normal.

[IanML]

Kenan, the cooling happens when the refrigerant passes through the expansion valve.  It then passes through the evaporator, which is the heat exchanger where the incoming ventilation air is cooled.  If that air is humid, some of that humidity condenses out, and that condensate is the subject of this thread.

The setup is illustrated here.  You will see that the condenser is the heat exchanger usually mounted in front of the engine coolant radiator.  When the system runs, that gets hot, so no condensation of water in the air will result at that point.