Dehumidifier.

[Christine J-R]

Hi we are brand new to Motor Homes and am looking for tips to avoid the dreaded damp. We will get a habitation certificate / check every year we will be regularly checking all the areas that we may get it and taking appropriate action. But my husband has hit on the idea of also buying a dehumidifier. The idea being to use it when we're out of the van. Can any of you advise me please? Many thanks

 

[Lenny HB]

No point the van will have permanent ventilation all you will be doing is trying to dehumidify the atmosphere.

 

[Podney]

As above,don’t bother it’s a waste of money,and unnecessary.

 

[Landy Andy]

I run a dehumidifier all the time my van isn’t in use. A dehumidifier inside can’t make the air any damper than it would be without it, and it causes air circulation which is a good thing. Far better than heating the van.

 

[Alanben]

Dont listen to the naysayers on here! We take one when winter touring, great for eliminating build up of condensation from cooking and showering etc especially on those wet dank days when opening roof vents allows more moisture saturated air to enter. Also when bringing in wet clothing adds to the damp atmosphere, we put wet clothing into the shower room with the dehumidifier which dries them in no time.
Obviously only usable when on hook up. A lot of people on the forum poo poo them! but they are wrong

^{_{Subscribers  do not see these advertisements}}

 

[Gaston aires]

Unless you want a dehumidifier, I wouldn’t buy one just for the van.
In fact I would wait and see what your needs are before you buy anything.
Lots of used twice items, nearly new for sale, especially drive away awnings.
Phil

 

[Dramfineday]

There's a load of videos on YouTube that'll give you guidance. Have a look there and then decide, I pull the cushions, seats etc away from the walls, open all the cupboards ( removing all towels, food etc ) and open the fridge doors. I then let the wind ( a near permanent feature where I live in Edinburgh) do its business ventilating the van. AND:

 

[rb62]

Dont listen to the naysayers on here! We take one when winter touring, great for eliminating build up of condensation from cooking and showering etc especially on those wet dank days when opening roof vents allows more moisture saturated air to enter. Also when bringing in wet clothing adds to the damp atmosphere, we put wet clothing into the shower room with the dehumidifier which dries them in no time.
Obviously only usable when on hook up. A lot of people on the forum poo poo them! but they are wrong

I think you will find that most people are talking about the use of dehumidifiers when the van is parked up and not being used rather than in your case when you are using your van.

 

[Alanben]

I think you will find that most people are talking about the use of dehumidifiers when the van is parked up and not being used rather than in your case when you are using your va

Yes your quite right, I realised that after posting.
We do use a dehumidifier when the van is laid up. We keep it on the humidistat setting, so that it only cuts in when the humidity increases.
I have a hygrometer which shows very low levels of moisture in the air. It works for me, so of course I would recommend using one.

 

[PP Bear]

Had this in the van for 10 years now and it’s brilliant and well recommended.

Its not a fast electric clear system, but removes loads of moisture, especially in the winter.

^{_{Subscribers  do not see these advertisements}}

 

[2657]

We had a static caravan in Brittany which was left unattended from Sept/Oct until May/June we used silica crystals in plastic containers spread around the van. Very similar to the device that PP Bear uses but without the circulation device, never had a problem with damp or musty smells and it was in a very damp area..
We have a 5'er in which we now live in Portugal, it is single glazed and under certain conditions the windows would be streaming if we didn't have a decent dehumidifier.

 

[Carolyn and Kev]

Had this in the van for 10 years now and it’s brilliant and well recommended.

Its not a fast electric clear system, but removes loads of moisture, especially in the winter.

View attachment 575911
View attachment 575912

As PP Bear as put it...we too use these and find them brilliant. Cheap to have and just amazes me how much moisture they pull out?

kev

 

[Christine J-R]

Dont listen to the naysayers on here! We take one when winter touring, great for eliminating build up of condensation from cooking and showering etc especially on those wet dank days when opening roof vents allows more moisture saturated air to enter. Also when bringing in wet clothing adds to the damp atmosphere, we put wet clothing into the shower room with the dehumidifier which dries them in no time.
Obviously only usable when on hook up. A lot of people on the forum poo poo them! but they are wrong

Could you recommend a suitable one for us? Thanks

 

[Alanben]

Could you recommend a suitable one for us? Thanks

we have a Meaco Junior Dessicant Dehumidifier. It's better than the compressor type as it works at colder temperature. and warms the air slightly. we use a tube to drain it into the shower tray. Its British made, and we have found Meaco to be very easy to deal with. they are recommended for boats etc
we purchased ours from Force4 chandlers, but here's a link to another company (Not used Appliances direct) OH AND WELCOME TO THE FUN
Broken Link Removed

 

[donkey]

we have a Meaco Junior Dessicant Dehumidifier. It's better than the compressor type as it works at colder temperature. and warms the air slightly. we use a tube to drain it into the shower tray. Its British made, and we have found Meaco to be very easy to deal with. they are recommended for boats etc
we purchased ours from Force4 chandlers, but here's a link to another company (Not used Appliances direct) OH AND WELCOME TO THE FUN
Broken Link Removed

Bit confused by info in instruction manual, it states: power consumption 650w.

But in the FAQ it states: A compressor based dehumidifier costs about 2-3p an hour to run.

So they do not actually tell you what this particular machine uses, but slyly quote figures for the much more economical compressor type?

650w is going to be nearer 20p per hour and that will rocket in a few months to around 30p.

Geoff

^{_{Subscribers  do not see these advertisements}}

 

[Alanben]

Bit confused by info in instruction manual, it states: power consumption 650w.

But in the FAQ it states: A compressor based dehumidifier costs about 2-3p an hour to run.

So they do not actually tell you what this particular machine uses, but slyly quote figures for the much more economical compressor type?

650w is going to be nearer 20p per hour and that will rocket in a few months to around 30p.

Geoff

Max consumption is 650 watts, on low speed is 330 watts which will remove 3.5 litres per day. When used on the humidistat setting it cuts in and out as required, so quite economical to run.

 

[donkey]

I suggest that to achieve those extraction quantities the ambient humidity would need to be near to 100% and temperature also at optimum. That is not the real world. Quite happy to be told differently, if someone with one of these could run a 24 hour test on one of these on low setting and measure the water collected.
I would also suggest that on the low setting the humidistat is unlikely to cut out on that setting, unless set at a very low humidity setting. And even on low the electrical consumption is close to £2 a day, rising to £3 in a couple of months.
I still favour the compressor type and use them regularly for various tasks.

Geoff

 

[Alanben]

I suggest that to achieve those extraction quantities the ambient humidity would need to be near to 100% and temperature also at optimum. That is not the real world. Quite happy to be told differently, if someone with one of these could run a 24 hour test on one of these on low setting and measure the water collected.
I would also suggest that on the low setting the humidistat is unlikely to cut out on that setting, unless set at a very low humidity setting. And even on low the electrical consumption is close to £2 a day, rising to £3 in a couple of months.
I still favour the compressor type and use them regularly for various tasks.

Geoff

Fair enough Donkey
You are obviously more of a technical expert than me. Im not sure what you are trying to prove. All I know is, I switch it on and it collects water, it keeps the van dry and my electrical consumption has not gone through the roof. If you favour the compressor type go ahead, it doesnt make any difference to my life.

 

[donkey]

Not trying to prove or influence anybody, but on low setting just short of 8kw of power per day.

Geoff

 

[Alanben]

Not trying to prove or influence anybody, but on low setting just short of 8kw of power per day.

Geoff

^{_{Subscribers  do not see these advertisements}}

 

[BouncyBoatFolk]

Dont listen to the naysayers on here! We take one when winter touring, great for eliminating build up of condensation from cooking and showering etc especially on those wet dank days when opening roof vents allows more moisture saturated air to enter. Also when bringing in wet clothing adds to the damp atmosphere, we put wet clothing into the shower room with the dehumidifier which dries them in no time.
Obviously only usable when on hook up. A lot of people on the forum poo poo them! but they are wrong

You may possibly be at odds with threads sentiment. For the situation you outlined that is probably a good use of a dehumidifier, when extra humidity is being generated. The OP would have to update their requirements, as usually this request is asked in connection with long term storage, when I would agree with the converse point of view, for every pint of water sucked out of the vans atmosphere, another one just replaces it, and boy is there plenty left in reserve in the planets atmosphere. Dry and cold is best, remove soft furnishing, open all cupboards, and bathroom doors. If possible, on days like today, dry and sunny, open up some doors and roof vents.
Additionally, for other reasons remove anything that critters could use as sustenance, best not to lure the little feckers in.
Mike.

 

[BouncyBoatFolk]

You may possibly be at odds with threads sentiment. For the situation you outlined that is probably a good use of a dehumidifier, when extra humidity is being generated. The OP would have to update their requirements, as usually this request is asked in connection with long term storage, when I would agree with the converse point of view, for every pint of water sucked out of the vans atmosphere, another one just replaces it, and boy is there plenty left in reserve in the planets atmosphere. Dry and cold is best, remove soft furnishing, open all cupboards, and bathroom doors. If possible, on days like today, dry and sunny, open up some doors and roof vents.
Additionally, for other reasons remove anything that critters could use as sustenance, best not to lure the little feckers in.
Mike.

Sorry, I just noticed your clarification, that's me late to the party as usual
Mike.

 

[Alanben]

Sorry, I just noticed your clarification, that's me late to the party as usual
Mike.

 

[Old Gibber]

I think the OP is confusing damp and condensation. The dreaded damp is caused by a fault in the sealing of the outer skin somewhere allowing water to get into the fabric of the walls veiling or floor. Nearly all motorhomes these days have inner linings to the walls and ceiling made of plastic or grp. Thus once water is trapped inside the skin it cannot get out, except by soaking down to the floor and rotting that. Once water has got into the fabric of the walls or ceiling, a dehumidifier will have absolutely no effect whatsoever other than to waste electricity.

Damp can occur inside if there is a leak in the water or waste system somewhere. This is usually quickly obvious when the van is in use, but if the water pump is switched off while in storage there should not be a problem.

Otherwise condensation can and does occur regularly when the motorhome is in use, and largely its harmless, and again because the walls and ceiling are impervious to water, it doesn't get into the fabric of the structure. Opening a window, roof light or door will usually clear condensation quickly. As has been said there is always a significant air flow through the motorhome, coming in through vents in the floor, and escaping through vents in the roof lights. Even here, using a dehumidifier is largely OTT. Before shutting the motorhome up after a holiday, do air the motorhome to clear any condensation first though, and maybe this is the only time a day's use of a dehumidifier is of value.

 

[Old Gibber]

As PP Bear as put it...we too use these and find them brilliant. Cheap to have and just amazes me how much moisture they pull out?

kev

Why does it amaze you? There is a plentiful supply of water in the atmosphere.

A bit of science puts it into perspective though. At 10 degrees C, every cubic metre of air will hold just under 10gm of water. Lets assume the inside of the motorhome is 2 metres wide, 2.5 metres high and 6 metres long. That's 30 cubic metres of air, each one holding 10gm of water making 300gm, or 300ml, just over a mug full. Dehumidifiers do not remove all the water vapour, therefore you would be lucky to get 150ml of water in your dehumidifier, or about half a mug full.

If you pull more water than that out, it simply proves you are trying to dry the atmosphere.

^{_{Subscribers  do not see these advertisements}}

 

[gpat]

Why does it amaze you? There is a plentiful supply of water in the atmosphere.

A bit of science puts it into perspective though. At 10 degrees C, every cubic metre of air will hold just under 10gm of water. Lets assume the inside of the motorhome is 2 metres wide, 2.5 metres high and 6 metres long. That's 30 cubic metres of air, each one holding 10gm of water making 300gm, or 300ml, just over a mug full. Dehumidifiers do not remove all the water vapour, therefore you would be lucky to get 150ml of water in your dehumidifier, or about half a mug full.

If you pull more water than that out, it simply proves you are trying to dry the atmosphere.

This is a good post. I can only add that I agree with those that say if the van is not leaking anywhere, there should be no excess moisture in the air and no need to dehumidify it.

 

[Richard n Ann]

Never used one and never had a problem. Electric is going up, so unless you have a specific problem save your money.

 

[Alanben]

Why does it amaze you? There is a plentiful supply of water in the atmosphere.

A bit of science puts it into perspective though. At 10 degrees C, every cubic metre of air will hold just under 10gm of water. Lets assume the inside of the motorhome is 2 metres wide, 2.5 metres high and 6 metres long. That's 30 cubic metres of air, each one holding 10gm of water making 300gm, or 300ml, just over a mug full. Dehumidifiers do not remove all the water vapour, therefore you would be lucky to get 150ml of water in your dehumidifier, or about half a mug full.

If you pull more water than that out, it simply proves you are trying to dry the atmosphere.

Fair enough
I have been using a dehumidifier for the last six years and before that I used it in our yacht for 15 years very successfully, it does the job for me and I can report that my driveway hasn,t turned to a desert but I have noticed that no clouds form over my van so perhaps your right

 

[Richard n Ann]

Fair enough
I have been using a dehumidifier for the last six years and before that I used it in our yacht for 15 years very successfully, it does the job for me and I can report that my driveway hasn,t turned to a desert but I have noticed that no clouds form over my van so perhaps your right

Try leaving it off for a week, see if it makes any difference.

 

[Alanben]

Never used one and never had a problem. Electric is going up, so unless you have a specific problem save your money.

blimey your from Derby, not Yorkshire!