Winter warmth

[Pete-B]

If I occasionally treat the inside of the van to some heat for a day or two during the winter months, would It be better to use the vans blowm air heating or use something like a seperate electric oil rad?

[snowie]

Hi Pete;

 

I'd do both, on the basis that it keeps the blown air system working, and also, by using an electric heater, you save some gas,

All the best

alan b

[mirage]

Why waste your money, in the past fifteen years I`ve never bothered even in the worst of weather and never had any problems, in fact you are probably likely to introduce more damp by heating and cooling.

No doubt you will get quite a few opinions on this topic.

[Mike B.]

I've just bought this-it doesn't really warm the van to any extent, rather just takes the chill off. At 500 watts though it's not using much more power than couple of lightbulbs and thought it would double as frost protection if I leave it on overnight in the really cold weather.

So far it seems fine-left it on half power for 3 hours and van was comfortable rather than cosy but definitely not frosty!

 

 

http://www.maillife.co.uk/view/product/maillife_catalog/1,930/DIS950

Mike

 

[Wills Wagon]

I wouldn't bother. Most motorhomes are ventilated so that the inside conditions are directly related to the ambient outside conditions and extra heat is not necessary. Adding heat increases the amount of moisture in the air so is not helpful. Like wise there is no need to dehumidify either. When you next use the van run the heating for perhaps a day with roof vents open to encourgae air flow and everything will return to normal. Of course if the motorhome is badly designed for instance no breathing areas under or behind beds or in lockers then moisture may well be a problem. We have had 10 years in four AutoTrails with no problems at all.

[Cliffy]

Pete-B - 2012-11-16 7:09 PM

 

If I occasionally treat the inside of the van to some heat for a day or two during the winter months, would It be better to use the vans blowm air heating or use something like a seperate electric oil rad?

 

If you are able to remove the upholstery and store it in your home then I would not bother with introducing any heat at all. If you leave the upholstery in the van, store it stood up in the centre area with plenty of air gap around each piece to allow air to circulate around them.

 

Cliff

[Guest peter]

mirage - 2012-11-16 7:31 PM

 

Why waste your money, in the past fifteen years I`ve never bothered even in the worst of weather and never had any problems, in fact you are probably likely to introduce more damp by heating and cooling.

No doubt you will get quite a few opinions on this topic.

I fully endorse this attitude. (not that anyone gives a toss) :D

[crinklystarfish]

As before, heating air enables it to carry more moisture which, when the heating is turned off, can no longer be carried. It has to go somewhere, and will usually condense on cooler surfaces.

Adding moisture to the interior is not a good thing.

Heat throughout the entire winter, or not at all.

[Brian Kirby]

Wills Wagon - 2012-11-17 9:22 PM

 

I wouldn't bother. Most motorhomes are ventilated so that the inside conditions are directly related to the ambient outside conditions and extra heat is not necessary. Adding heat increases the amount of moisture in the air so is not helpful. Like wise there is no need to dehumidify either. When you next use the van run the heating for perhaps a day with roof vents open to encourgae air flow and everything will return to normal. Of course if the motorhome is badly designed for instance no breathing areas under or behind beds or in lockers then moisture may well be a problem. We have had 10 years in four AutoTrails with no problems at all.

Yes, all motorhomes have permanent vents. These tend to negate the benefits of de-humidification, because external humidity continually permeates in. In effect, you end up trying to dehumidify our usually humid atmosphere and not just your van. It is true you won't see mildew, but the de-humidifier will be working far harder than it needs to. They also become less efficient at lower temperatures, so I think are not such a good solution.

 

It is not correct, however, that heating air increases the amount of moisture it carries. It does not. The amount of moisture in the air remains broadly constant irrespective of temperature.

 

What changes is its relative humidity (RH), which is a measure of how much moisture the air could carry at a given temperature. The warmer the air, the more moisture it CAN carry, but for it to gain moisture, there first has to be free moisture somewhere for it to take up.

 

Our climate is famously variable, and our RH levels are generally high. That is why we so often get evening and morning mists in autumn, as we cool into winter. The air warms during the day, takes in free moisture, and then cools into evening when eventually its RH exceeds saturation, and the humidity condenses in the air to become water droplets. Heating that cool, saturated, air actually lowers its RH. This is one of the reasons why heated buildings in winter often have uncomfortably dry atmospheres, and is why commercial air-conditioning systems have humidifiers to raise to RH to a more comfortable level.

 

The problem is that the air in unused vans changes slowly, meaning it's moisture content also changes slowly, whereas the van's general temperature will fluctuate much more quickly: for example between early afternoon on a cold but bright and sunny day, when the van will warm up, and the early hours of the following morning when it may be frosty outside, and the surface temperatures in the van sharply lower. These changes of temperature will change the RH of the air in the van, lowering it as the van warms, and raising it again as the van cools.

 

Any problem that may arise will be after a period of relatively mild weather - when the moisture content of the air generally, and so by degrees the air in the van, will have risen - that is followed by a cooler period with frosty nights. Then, the sharp fall in temperature during the night will result in condensation on the rapidly cooling surfaces of the van, both inside and out. Inside, once the condensation forms, the surfaces will tend to absorb moisture, making wooden elements swell slightly, and giving soft furnishings that cool, slightly damp, feeling that suggests they need "airing" - which they do. Under these conditions, if mildew spores are present (likely) they will grow. Outside, that condensation will be recognised as dew.

 

If low level frost protection heating is provided in the van, it will keep the inside surfaces, and the internal air, that bit warmer (so keeping the RH of the air that bit lower), to prevent condensation. That will ensure mildew cannot become a problem, and will also help prevent those slightly sticking locker doors in spring, and the joints in any natural timber elements from opening.

 

Whether you need to do this depends on where in the country you live, what kind of winter weather you experience, and the construction of your van. Generally, the colder it gets, the dryer the air, and the lower the risk. On the other hand, those near the west coast, and especially in the south west, where humidities are more often high and the weather more often mild, but subject to sudden, cold, sometimes snowy, periods, are at higher risk.

 

So, some leave their vans as they are and have no problems, while others doing the same thing may find mildew. There is no "one size fits all" rule, and what works for one van in one location is unlikely to translate into the correct remedy for all vans, everywhere. Horses for courses, see! :-) You just need to apply common sense and local knowledge.

[747]

I use occasional heat but only during prolonged spells of freezing weather.

 

The talk of buying and using a dehumidifier has always puzzled me. Mostly because the only dampness I encounter with my van is due to condensation from cooking and breathing while using the van in cold weather.

 

Instead of an expensive dehumidifier, I place 3 bowls of salt in the van. When they go crusty, I bring them in and put them on a radiator to dry out and then replace them. This problem of warm air holding more dampness is true but unavoidable. Today is cold and sunny here but my van is pleasantly warm inside due to the sunshine streaming through the windows.

 

You must have the choice of hooking up your van so my recommendation is to hook up. Firstly this will keep your batteries topped up. Nothing kills a battery better than a bad winter. If your van battery does not charge from hookup then modify it to do so or use a separate charger.

 

A full fuel tank can prevent moisture building up in the tank. I know it is expensive to fill but it will probably be more expensive next year if you have to top up for a trip.

 

When you get the odd sunny, mild day, open up a few windows to get some fresh air through it. Have all cupboards and locker doors open.

 

Better still, use it over the winter.

[Guest JudgeMental]

no never dont see the point...

[maggyd]

In either caravans or motorhome we have never heated it in winter, we leave the cupboards open and have a couple of moisture traps on trays which we empty frequently as needed, the cushions we have always stood on end away from the walls and never had any problems :-) as others have said introducing heat only causes condensation problems.