Electric blankets

where can old people buy duvets which restore thermoregulation or raise skin temperature above their (low) autonomous levels?

"A campaign will try to avert some 20 deaths and 5,000 fires a year that occur as a result of using old or faulty electric blankets. "

Wish they'd do the same with people.

could try argos

:)

The cable starts off with electrical insulation on the outside but wear and tear eventually compromises it.

You would know if it was mains isolated low voltage since there would be a fairly chunky mains transformer involved. The original Windak brand was the only one whose main claim to fame was that it didn't electrocute people in bed - early ones had 3 settings later ones were continuous.

I haven't seen any modern ones that were not a trivial combination of diodes and resistors across the mains with a thermal fuse somewhere. The main thing that seems to go is the thermal fuse after 2 years or so. I suspect it is built in obsolescence by design. I bought spares from my favourite RapidOnline when my mum's blanket controller failed.

Silentnight make one with a 3 year warranty and 3 heat settings. Haven't tried it so they may be very low, low, and quite low, but I doubt it.

and freeze round the deges!

I use a hot water bottle. It goes in the microwave, no pouring involved. I'd be very surprised if it weren't safer than an electric blanket.

NT

I'm surprised it doesn't explode!

strange thing to say.

It delivers far more heat than an electric blanket too

NT

Can you please give an example of a retail product which delivers that performance please?

And is it certified safe if an old person accidentally heats it for 10 times the specified time?

I don't know what that means. And life is too short for stupid questions

Ah, an even more stupid question.

I am sorry if I am not as clever and articulate as you. Please let me try again.

You said "it delivers far more heat than an electric blanket too". What is "it" please?

Sorry, I didn't realise you are also an expert on risk assessment.

Stupid? How so? Plenty of incidences of fires due to these ?bottles?.

Tim

====snip====

That's a rather expensive way to pump energy into a hotwater bottle full of water. However, it does allow you to heat the water to a fairly precise temperature provided you're prepared to experiment with a full range thermometer (0 to 100 deg C). You need to know the volume of water being heated to within a few percent.

Surprisingly, it's possible to fill a hot water bottle straight from the tap and judge by feel to within 5% or so. All you need then do is try different times on full power until you get a comfortably hot water bottle temperature (the actual water temperature might need to be a good

Obviously, the water fill temperature will effect the heating time but it shouldn't be too difficult to approximate an adjustment to compensate for warm summertime mains water during brief cold snaps - winter mains water temperatures will be consistent enough to use a standard time with a standard fill.

Having explained the benefit of using a microwave oven to heat a cold filled hot water bottle to get consistent temperatures, I have to mention that it'll work out almost twice as expensive to do it this way versus the more traditional electric kettle heating of the fill water.

If your concern with using a kettle to heat the water up is one of the scalding risk, there is a much safer way to fill from a freshly boiled kettle of water followed by topping up with cold to get the right temperature as my wife insists on doing and that is fill the kettle to about two thirds of what you need to fill the bottle and after letting it boil, add about 50% more cold water to the kettle (give or take according to the desired final temperature) so that when it comes to the business of filling the water bottle from the kettle, the risk of scalding is greatly reduced.

I use a 1.7L jug kettle filled to about 1.2L which leaves enough room after boiling to add another half litre or more of cold before pouring it into the hot water bottle. Overfilling a kettle is only of consequence if you intend to bring the whole 1.9 or so litres in a 1.7l kettle back to the boil.

A microwave oven is a far more efficient way to boil/heat water then any kettle. So don't drivel on.

Um, I suspect that the ?bottle? being referred to is a wheat or millet grain filled one.

For example,

I?m not even sure if conventional hot water bottles are suitable for microwaving. I know that ours has a metal inset in the neck that might overheat in a microwave.

Tim

My bad! It just never occurred to me that *anyone* posting here would be

I think all of our rubber/plastic hot water bottles (3 or 4 afaicr) use plastic threaded inserts so could be heated in an older, more capacious microwave oven (might require a microwaveable cage to confine the bottle's dimensions to a more cubic shape if you want it to rotate *with* the turntable in a modern cheap 'n' cheerful oven).

However, I'd have thought it more practical to simply heat a plastic measuring jug's worth of the required amount to fill the water bottle to the desired level (somewhere between an inflated puffer fish and a floppy Dover Sole), in which case, you only have the downside of it costing nearly twice as much as using an electric kettle to energise the water molecules to a comfortable temperature as perceived on the external surfaces of the hot water bottle.

Quite frankly, anyone who gifts such grain based microwave heated thermal storage 'toys' to their elderly relatives as a 'safer' alternative to the traditional hot water bottle, is taking a very real risk of facing a charge of accidental manslaughter or worse should the inevitable happen. Only a fool would place their elderly relatives at such risk in this way.

that's a wheat bag not a water bottle

NT