V6 peculiar leak from front aircon unit

[cue8all]

Hi, i found that when i put the air con on 18 that i had a puddle form under the van. Upon further investigation it appears that anything from 18.5 upwards = no leak (or at least just the odd drip but on 18 (the lowest setting where it's sending cool air into the interior) there is a constant leak of fluid. I'm guessing that a seal may have gone inside the front air con unit but wondered if anyone else has had the same issue or any thoughts. I can probably access it myself but don't want to start something I can't finish.

[wonkanoby]

may just be condensation

if the gas was leaking it would not get cold

[cue8all]

Definitely not condensation. I thought (hoped) that too but i've spent this morning crawling under the van with a torch and it's definitely a leak as it only happens on a specific temp, when the fan is working hard at the lowest temp setting, above 18.5 no leak, 18 leak.

[jaylee]

What happens when you put the vent on recirculation on the "specific temp, when the fan is working hard at the lowest temp setting"?? Do you get the same result??

[cue8all]

yep, tried all configurations i could think of. The leak comes through one of the plastic 'drain holes' underneath the unit and also forces its way between the plastic casing and one of the metal connector pipes. It could just be that a seal has gone and under pressure it leaks but it seems strange that it only does it on the lowest temp setting. i'm wondering if it uses a different set of piping to cool vs heat as i only got the van in Sept and haven't put it on the lowest setting until now so it might have been that way for months without it showing up.

[the laird]

Are you losing coolant.is the fluid coloured or clear?are you having to top up header tank?
If you're not dropping level doubt that it's coolant.if its clear you could prob find its defrost of condenser /evaporator in a/con system

[cue8all]

from what I can tell it's clear and there is no smell of coolant from the liquid but it only started yesterday and it's only losing a few teaspoon full's worth at the moment so there's no discernible change in the coolant level. i'd ruled out condensation simply because the leak get's immediately worse as soon as you hit the 18 button, there's no delay while it changes temp from further up the range, also there's no condensation on the metal pipes leading into the the housing. I guess it could be forming inside the housing and running down but it just seems excessive, the drips are almost enough to form a constant run when the fans on full, which is why i suspect a leak under pressure. If anyone else has a V6 ( and a few mins to spare) it would be interesting to compare as if it's condensation it should happen on all of them. Just get the engine up to temp with the air con off then turn it on and set to 18. The drips can been seen in between the front wheels and if you lift the bonnet they'll be coming from the bottom of the a/c unit (by the two metal pipes leading out of it).

[Northern Bongolow]

is it from the windscreen drain pipe, this drains from a hole at the bottom centre of the screen down a drop pipe, this is fastened to the driverside of the front heater housing.

[cue8all]

it's not that pipe - i located it and moved it out of the way as it's not connected to anything at the bottom end

[jaylee]

OK, here is my thoughts..

Your fan is on full pushing the maximum of damp air into the evaporator causing moister to be sucked out by the cold unit before the chilled dry air is pushed further into the cab, thus causing the noticeable evaporator water drip from the front housing..

If you had the fan setting low whilst driving at a certain speed? The "ram of air" would probably do the same thing, but you would not be aware of the drip of condensed water...

Sounds to me like your AC system is working fine...

Do you get a drip from the back unit when the fan is on full? It might not be so noticeable with drier air in the van passing through the rear vents though..?

[cue8all]

like your thinking. I reckon I'll try the a/c on 18 for a few days and see if there's an obvious drop in coolant level. If not I'll assume i'm being paranoid having read so many articles on the site about bongo's and coolants! Not noticed anything from the rear unit and I tried with it both on and off. It's freaked me out because it's coming from both what looks like an obvious drain point but also from the plastic housing join and down one of the metal pipes. If it were just the drain point i wouldn't worry and accept it's just condensation.

[jaylee]

You should always keep an eye on the coolant level....

Regarding the AC..
If there is a gap water drawn from the evaporator will find a way out.... http://lushprojects.com/bongopartsmk2/c ... mgno=.html

[cue8all]

Thanks for the schematic, i'd looked on the site earlier but couldn't find it. The fluid is coming out from the clamp and the pipe at the bottom. It could be that under pressure from the fan the fluid is escaping from the joint or it could be just condensation, as you say. I'll see how things go. The van has a coolant level alarm and now i know what's beneath the plastic casing i have a better idea of what might be going on.

[jaylee]

The van has a coolant level alarm and now i know what's beneath the plastic casing i have a better idea of what might be going on.

Just to clarify, the vans coolant does NOT go anywhere near this evaporator housing... The chilled air goes on past the heater matrix in the cab which when set to cold is covered by a flap that controls the temperature out through the vents...

[mikeWalsall]

All the cars I have had with A/C have left a puddle of water underneath when parked ..

Even in winter I leave the V6s A/C on, and there is always a patch of water on the drive under the condenser ..