Condensation

[Buckman]

No issue with condensation while caravan was in storage however using it had present and condensation is severe around the bottom of the three front windows, the kitchen window and bedroom window. The air con is running on fan only so only recirculating air. Bathroom Heki is open about 2 - 3 inches. No vent holes are blocked. We have never had this issue with previous winter trips at same time of year in same caravan. Hoping it is not window seals however on a 4 year old caravan they should still be okay.
I have now put bathroom and kitchen windows on night latch and dropped night time temp from 18C to 17C. I had to reset the ALDE and forgot to adjust the night time setting down to 17C. I am thinking that maybe during the night when it si really cold the night time temperature was too high. Maybe 17C is still too high?
Any suggestions would be welcomed. Thanks.

 

[GeorgeandAde]

Popped down to ours in storage yesterday.
All cupboards and drawers open.
Mattresses standing upright on floor.
No heating,air con or moisture traps.
Can't open windows or rooflights whilst in storage.
Everything's fine.
No condensation or nasty smells.

 

[Buckman]

Popped down to ours in storage yesterday.
All cupboards and drawers open.
Mattresses standing upright on floor.
No heating,air con or moisture traps.
Can't open windows or rooflights whilst in storage.
Everything's fine.
No condensation or nasty smells.

We don't have an issue with the caravan when in storage.

 

[MikeyW]

We are in our caravan over Christmas and we also have condensation. We've always had it when we use it in the colder months. No problems in storage. We only open the kitchen window and roof above the cooker when cooking. I tend to just go round with some kitchen roll and mop up the excess. Other than that we just live with it.

 

[Buckman]

I was also thinking of putting air con on night mode which is silent to help reduce moisture. First time we have had this issue in the winter months.

 

[MikeyW]

We don't have air con. To be honest we seem to get more trouble with the windows when we open them especially the front three. The caravan is 10 years old now and the front windows have leaked a few times. They are okay now but I'm reluctant to open them in case they don't seal when closed. We cook in the caravan and my wife talks a lot so it creates a lot of condensation but it's never really caused any problems. I also find that after a few days of use it seems to improve.

 

[Hutch]

We find every now and again we get condensation around the windows, not surprising, two people, a dog, cooker going on gas, opening and closing the door, it disapears afer a while, get the heating going and all is well.

 

[Buckman]

Strangely the two front side windows on the near and off side there is no condensation at all.

 

[Jcloughie]

Adjusting the temp will make little or no difference. Condensation can only form if moisture is present in the air. And then it will hunt out and form on the surface with the biggest temperature differential.

Moisture is formed by breathing, cooking and climate humidity. You can’t stop that so you need to take measures to minimise. Air circulation and enough ventilation. But in your case you already have the tool to do the job. Air-con. Can be great in hot weather to cool you. But it also works as a dryer. This is why your car will automatically turn the air con on to demist.

Your air con unit should collect excess moisture and drain it to the outside.

There might be a problem if you overdo the ventilation and use the air con as one will work against the other. But I would open a widow while cooking.

John

 

[RogerL]

The air-con compressor will switch off at about 5 degrees C (to avoid icing up) so may not be on.

 

[Buckman]

The air-con compressor will switch off at about 5 degrees C (to avoid icing up) so may not be on.

Thanks for the reminder however last night I think it was down to 7C. Tonight and rest of our stay until Tuesday it is not supposed to drop lower than 6C. I will update tomorrow after having various windows on night latch.

 

[Jcloughie]

The air-con compressor will switch off at about 5 degrees C (to avoid icing up) so may not be on.

I thought that can’t be right. Car air con keeps working to below freezing. I did have one car that froze up but that only happened on very humid summer days as the condensate froze before it cleared. That was a design fault. The gas should not freeze.

But looking at the Dometic manual that actually says it only operates above 16c! The winter setting only moves air around. I think they are missing a trick if their equipment will not operate as a dryer when most needed.




John

 

[Buckman]

Our previous Dometic 2200 Freshjet removed humidity, but our Truma does not have that facility unless you put it onto air con cooling mode. Using the manual side as can turn down the fan.

 

[Jcloughie]

Our previous Dometic 2200 Freshjet removed humidity, but our Truma does not have that facility unless you put it onto air con cooling mode. Using the manual side as can turn down the fan.

The extract I posted was from Dometic.

John

 

[JTQ]

First, I don't think the window seals aging has anything to do with the issue.

Some basics:
Air holds moisture vapour, the more it heats the more it can hold, and conversely the colder the less.
Condensation occurs only where the air has 100% of the water it can hold but is chilled further.
___________________________________________________________________________________
My reasoning:
Presently the ambient temperature has been "mild" so the air most probably is quite humid anyway.
Unlike really cold winters when things are so cold the air becomes dried out.

The point I am making is presently you are camping in water laden air.

In the van, you warm that air, so it can and will take up more water, simply because it is hotter, and you breathe etc.
So probably the internal air is particularly damp, even compared with your previous winter camping.

It then only needs to chill against the poorer insulated bits in the van, windows, window seals, door frame and anywhere there is embedded structure, and it will shed condensation.

Ventilating now, even though needed, will only bring a small relief, as the air is damp out there.

The real issue you have is the elevated temperature you are trying to camp with under the present conditions, the lower you bring it the less condensation you will encounter.

The AC can present a cold surface on which condensation will form, so if left running it will ease things a bit.
IMO, something of an endless struggle, in the van needs ventilation, so despite the AC stripping some, you are bringing more moisture in and adding to it yourselves.

Hope for a change to bitterly cold weather from this mild spell, then the intense cold will really dry the air out well; then keep the van well vented to pull that lovely dry air into the van, and condensation will be less of an issue.

Presently drop the temperature, or live with lots of condensation; run the AC continuously will ease it a bit.

 

[RogerL]

I thought that can’t be right. Car air con keeps working to below freezing. I did have one car that froze up but that only happened on very humid summer days as the condensate froze before it cleared. That was a design fault. The gas should not freeze.

But looking at the Dometic manual that actually says it only operates above 16c! The winter setting only moves air around. I think they are missing a trick if their equipment will not operate as a dryer when most needed.

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John

It's not the gas inside the system that freezes, but the air going through the cooler and the ice then blocks the airflow.

Your car aircon may appear to work below freezing but the compressor won't be working and the cold air is simply ambient.

 

[otherclive]

I thought that can’t be right. Car air con keeps working to below freezing. I did have one car that froze up but that only happened on very humid summer days as the condensate froze before it cleared. That was a design fault. The gas should not freeze.

But looking at the Dometic manual that actually says it only operates above 16c! The winter setting only moves air around. I think they are missing a trick if their equipment will not operate as a dryer when most needed.

View attachment 2706


John

Cars will show the ON light but inhibit the compressor at external temperatures below 4degC. At lower temperatures the efficiency falls off markedly.

 

[Buckman]

It's not the gas inside the system that freezes, but the air going through the cooler and the ice then blocks the airflow.

Your car aircon may appear to work below freezing but the compressor won't be working and the cold air is simply ambient.

TBH I think it is because the drain pipes may freeze causing water to enter into the caravan.

 

[otherclive]

TBH I think it is because the drain pipes may freeze causing water to enter into the caravan.

But what night time external temperatures have you had where you are pitched. With the heat on in the caravan it would need to be quite a cold night to start freezing drains? Lowest we’ve had around here recently was -2 deg c.

 

[Darren.H]

We are living in our Coachman Pastiche 2016 with Alde full time, wifey and me., cooking and showering every night.
All our windows and roof lights are closed all night, caravan is kept at least to 16 degrees via a tower fan heater, the Alde heating is off, no condensation whatsoever, our location is Cornwall, when we had just alde heating for night time we didn't have condensation either.
The only thing we have done from standard is put a tea towel on the floor at the base of the oven because there's a draft that cuts your feet in two!

Could it be whilst in storage your soft furnishings have absorbed moisture via the drop vents and your caravan internally is drying out???

 

[Jcloughie]

It's not the gas inside the system that freezes, but the air going through the cooler and the ice then blocks the airflow.

Your car aircon may appear to work below freezing but the compressor won't be working and the cold air is simply ambient.

I did actually say the same Roger, But freezing is worse in more humid conditions if, as in the case of my Citroen XM, the evaporator is poorly designed and the humid air freezes before it runs from the condensate drain, this would happen on very hot days. I agree that the compressor will turn off below 4C but. as OC says this is taken care of automatically. (or should be). So far as the user is concerned, the aircon can remain on.

But that's on cars. for some reason the Dometic roof unit does not operate below 16C, which I find odd. But the OP has a Truma unit.

John

 

[Jcloughie]

Cars will show the ON light but inhibit the compressor at external temperatures below 4degC. At lower temperatures the efficiency falls off markedly.

Correct.

John

 

[Buckman]

But that's on cars. for some reason the Dometic roof unit does not operate below 16C, which I find odd. But the OP has a Truma unit.

John

To be pedantic only the cooling side will nto work and the same probably applies to many other air cons. The Dometic 2200 Freshjet will still remove humidity, add heat to the caravan and fan will operate.

 

[RogerL]

To be pedantic only the cooling side will nto work and the same probably applies to many other air cons. The Dometic 2200 Freshjet will still remove humidity, add heat to the caravan and fan will operate.

It can't remove humidity if the cooling isn't operating.

 

[Buckman]

It can't remove humidity if the cooling isn't operating.

Agree about our Truma, but Dometic Freshjet 2200 removed humidity without cooling down. It had the separate function. Not sure about newer models. On the Truma we need to select manual air con cooling