A few months ago I purchased a Floe device ( Floe ) for removing residual water left in the supply system after draining down in the traditional manner.
Having recently purchased a digital air compressor I thought I would give the Floe a test run.
After studying the enclosed DVD I set to work pressurising the system after having close off all the taps and closing the water heater dump valve.
Being unable to pressurise the system properly I went into the van to investigate where I discovered I had not closed the shower tap and the bathroom was soaked in water.
After drying the bathroom I carried on doing the other taps and the water heater but because most of the water had come out of the shower there was only about 25mls or so of dirty brown water left in the system which I wouldn't have fancied drinking.
I would estimate that including the water in the washroom and that in the water heater there would be about 200mls remaining in the system which is enough I imagine to cause problems in a cold winter.
As the van hasn't been used for a couple of months due to cancellations because of the weather/flooding then some of the remaining water will have evaporated I suppose.
So in conclusion the Floe does actually work in removing water left in the system.
Next time I use it I will make sure the taps are all shut so I can measure more accurately the remaining water.
I shall sleep a bit easier in my bed next winter knowing that there is much less likelihood of frost damage during any cold weather we may have.
The Floe is around the £40 mark which for what it is is quite expensive but still less costly than having a frozen water system repaired.