Screen - Excessive moisture

[Monkster1]

Hi all, I've noticed again this winter as the temperature drops away over night, the inner windscreen has a fair amount of moisture - enough to have to use a 'T' style squeegy and a paper towel to remove the excess before driving. I'm thinking there must be moisture within the van somewhere in order that it happens. I know this van inside and out now, I've had it apart so many times and I am only aware of an area of slight moisture within the bottom of the o/s rear panel behind the back wheel (pics attached). Nothing has been spilled and it's been vapour barriered throughout the rear. The cab area is totally standard other than for a leisure battery and electrics under the drivers seat. Care was taken to route the cables through the N/S main bulkhead grommet.

I park forwards against the front of our house so I know it can get cold and it is North facing so doesn't see much temperature rise in the day time. I've never had this issue with any of the cars I've had so I'm just curious as to whether its something that effects other guys vans? I wondered whether there could be moisture in the drivers floor mat but they are bone dry. The pictures show as I found it, and after wiping away the residue. I wouldn't say it was 'wet'. Is this a common problem or just a winter one?

2018 Highline PV Day van conversion. Thanks for your thoughts, Russ

 

[Loz]

Is it wet under the front carpet?

 

[Monkster1]

Hi Loz, to be honest its the one thing I haven't done as it'd be a big job to do it properly. The van is on a very slight up hill gradient and I can feel under the rubber carpet at the back of the seats and the mid floor section and nothing damp felt. I'm really conscious about wet feet and spills etc to the point where I have an old Volvo passenger mat which is high-sided for keeping moisture away from the carpets.

This ties in with another thread I'm discussing relating to vents and circulation of air. We've only slept in the van once this year back in July for a few nights and as the previous year we got a certain amount of moisture over the windscreen which was expected. I've got the Heko wind deflectors and an opening side window so we had air coming in but only from the front area. In the grand scheme of things I'm pretty new to vanning so still picking up sleeping / camping tips etc. Could really do with another vent area at the back. I've got the barn doors so difficult to leave one cracked open when sleeping.

 

[DXX]

Try putting a heater inside while parked, get it good and hot and then ventilate. If you have a humidity meter you’ll see when it’s dry (cheap on ebay).
Once dry remove the heater and close up. If the condensation re-appears there is water getting into the van.
One possibility is a build up of leaves, mud and general grime in the scuttle allowing water in through the ventilation, as your van is only 2 years old it shouldn't be that dirty.

 

[Superowls]

I get the same in mine, not overnight though - its always clear

But when I drive to work and park it up it's full of condensation on inside of screen when I return to it at end of shift
I usually end up sat for 5 mins with blowers on full & heated screen on

 

[DXX]

VW Owners Manual states that air con should be left running assuming you have it installed, this makes a big difference.

 

[Monkster1]

Thanks guys. I do have a diesel heater onboard. I installed it last summer ready for this winter but its been disconnected for a few months whilst messing with the interior. I've just given it a 40 min run without issue. Just the slightest bit of misting but I put that down to me sitting in the cold van. Didn't want to leave it running unattended and it was pulling some amps until it got up to temp. I know a dirty windscreen can hold moisture but it got a good clean this morning.

Scuttle is clear with good air flow. The heater and air con are both functioning properly and no fusty smells occurring. I wonder if its just the outside temperature and damp in the air. I feel sure it happened last year a few times because I was worried I'd made a cock-up putting the roof rails on. It appeared not, but as shown in the pics, there's a bit of moisture from somewhere.

 

[Skyliner33]

Have you taken the ends off the dash (the bit the airbag keyhole is on (passenger side) and looke for water coming down the A pillars? Sometimes water can get in the roof bar holes and makes its way down here onto the carpet just below the dash.

 

[Monkster1]

No, That's another great suggestion.

Thanks all.

 

[saxoboy]

Another idea....do you have roof bars on?......My windscreen did the same last winter, I kept seeing water at random areas in the van, I took the bars off, and replaced the original bolts with threaded bar and new rubber washers then silicon sealed the hole before before tightening them down (tip that is mentioned on this forum...great idea )...now my screen is clear every time and there are no signs of water inside the van...worth a try...Matt

 

[Monkster1]

Hi Matt, Yes. I'm thinking the bars might have to come off in spring for a proper check over. I did the usual though, clean the threads, apply Sikoflex into the hole and applied it to the outer threads of the bolts, and I gave it time before using them. I also gave it the watering can test lol.

 

[Dave Mac]

Normally all that moisture would be dispersed on the bare metal in the van, but when we insulate and carpet line vans the glass becomes the coldest surface thus the condensation issue. Just my opinion I’m sure others have theirs.

 

[Simon Kay]

I leave silica bags on the dashboard just to capture any 'loose' moisture that's around, seems to work so far, available from amazon etc..

 

[Superowls]

Normally all that moisture would be dispersed on the bare metal in the van, but when we insulate and carpet line vans the glass becomes the coldest surface thus the condensation issue. Just my opinion I’m sure others have theirs.

That could be a fair point.....I insulated mine within an inch of its life

 

[Superowls]

VW Owners Manual states that air con should be left running assuming you have it installed, this makes a big difference.

So you should leave air con in all the time....even if not needed?
Mines hardly ever on so if that's a cause that would explain it

 

[Monkster1]

Yes, that makes a lot of sense Dave. The van has only been carpeted since September and it feels like the inside temp is very stable. The door metalwork seems to be dry so maybe the glass takes the biggest hit as it is in direct connection to the outside elements.

 

[Monkster1]

So you should leave air con in all the time....even if not needed?
Mines hardly ever on so if that's a cause that would explain it

I understand you should use the Aircon regularly all year round to keep it working effectively.

 

[Superowls]

I'm off outside to stick dodo mat onto the inside of my windscreen......hopefully that will do the trick

 

[Monkster1]

I leave silica bags on the dashboard just to capture any 'loose' moisture that's around, seems to work so far, available from amazon etc..

I have some in the garage loft. So many great ides, thanks guys.

 

[Superowls]

I understand you should use the Aircon regularly all year round to keep it working effectively.

Will give it a try but really goes against the grain.......I'm a Yorkshireman!