Is using low wattage tube heater worth while?

So long as the plumbing has been drained I can*t see the point of heating the caravan while it's in storage. Perhaps someone will enlighten me.

I've had my caravans out in the open for over 30 years and even when the temperature has dropped to -15° on isolated occasions I only had a problem once because I had forgotten to drain the boiler.

I’d recommend that if you have a toilet flush system which uses the onboard tank that folk make sure the toilet pump is completely empty when draining down. Just flush till it runs empty.

In 40+ years of owning LVs we have never put heating on over winter. If you follow the correct procedures of preparing the vehicle for winter you should not encounter any problems.

We currently live in Scotland and previous to that in northern Germany where winter temps can drop to -15c at nights. here in Scotland where we live -10c is common place. Our vehicles sit outside the house so it would be easy to have heating on but its just not needed. 

Like others if its a nice day we go and open up the skylights and windows or door and give the van a good airing. we don't remove the cushions but we do pull them away from the vehicles walls. we do drain down and leave taps open as is the toilet blade left open. we remove all food and especially tins. We do check the water pump filter to make sure there is no water in it as that can freeze up.

We no longer have a caravan but in all the years we had one we never heated the inside whilst in storage.  We also had a full cover which worked very well.  We removed internal cushions over winter and thoroughly drained down all the water and toilet system.  We never had a problem with mould or damp so I don’t see the point of heating (however small) the inside.  As others have said, we did like to give a change of air on a nice day occasionally.  

Whilst not related to heating and the original question, if it's considered essential to keep a movement of air, is it worth using covers for the refrigerator vents during winter?

In my opinion, yes, as they help keep snow, rain, dirt, vermin and insects out. There are plenty of other vents in a caravan to provide air flow. However, follow the fridge manufacturer’s guidance as some say the covers should also be used when the fridge is in use below certain temperatures.

Thanks Tom, you’ve just reminded me to put mine on. Daft as it sounds caravan fridges’ cooling systems can be adversely effected by very cold ambients air temperatures which can inhibit both their functionality and efficiency.

The same problem of cooling at low outside temperatures also applies to our domestic/home fridges and freezers. If you have the spare one in the garage it will not run correctly if your garage gets to cold. You have to consider the climate class/rating:-

https://procoolmfg.com/refrigerator-climate-class-sn-n-st-t/

Colin