6 things people do in hot weather that don't work (and cost you money)

Temperatures could reach 36°C on Thursday, and most of England is under an amber heat health alert until Friday evening.

It's already been an unusual summer. The UK has now had 35 days above 30°C this year, which is more than any year on record, beating the 34 days set back in 1995.

So a lot of us are trying to cool our homes down. And some of the things we reach for either don't help, or make things worse while adding to the electricity bill.

Myth 1: a fan cools the room down

It doesn't. Government guidance is clear that fans don't cool rooms, they just move the air around. What a fan actually does is help sweat evaporate off your skin, which is why you feel cooler standing in front of one.

That matters for two reasons. Leaving a fan running in an empty room does nothing at all, and the guidance also says not to use one when the air temperature is above 35°C, because at that point you're just pushing hot air about.

The good news is that a fan is cheap. At the current price cap a 45W fan costs a little over 1p an hour, so running one for 12 hours comes to about 14p. If you've been avoiding yours because you're worried about the cost, that's the number to know.

Myth 2: point the fan straight at you all night

Government advice says not to aim a fan directly at your body, because it can dry you out and leave you dehydrated without you noticing.

Fire services also advise against leaving a fan running overnight or while you're out of the house, since the motors can overheat.

Better to set it off to one side so the air moves through the room rather than straight at you.

Myth 3: throw all the windows open

This one depends entirely on whether it's hotter outside or inside.

During the day, when the sun is on your windows, opening them lets hot air in. The advice is to keep windows that face the sun closed while it's hot, and draw the curtains or blinds on any window getting morning or afternoon sun.

Then open the windows at night once the air outside has cooled, and try to get a through-draught going by opening windows on opposite sides of your home.

Myth 4: a freezing cold shower is best

It feels like it should be, but the physiology works against you. Very cold water makes the blood vessels near your skin narrow, and that's the body's cold response. Narrowed vessels move less heat from your core out to your skin, so the heat stays in.

Research suggests a tepid shower at around 26 to 27°C is more effective, because it brings blood to the surface to cool without triggering that response.

A hot shower doesn't work either, because you're adding heat to a body that's already trying to get rid of it.

Myth 5: turn the fridge and freezer down

Turning the dial down doesn't cool your kitchen and it won't keep food safer than the normal setting does.

What it does do is make the motor run harder and longer, which uses more electricity. And because a fridge works by moving heat out of the cabinet and into the room, running it harder actually puts more heat into your kitchen.

It's worth checking your fridge and freezer are working properly in hot weather, and making sure the vents at the back aren't blocked. But the setting itself is best left alone.

Myth 6: a cold beer cools you down

The cold drink helps for a moment. The alcohol doesn't.

Alcohol makes you lose more fluid, and dehydration is the thing that turns uncomfortable heat into something that makes you ill. Health guidance for hot weather specifically says to avoid drinking too much alcohol.

Cool water is better, and research suggests cool water is absorbed more efficiently than ice-cold water.

What actually helps, and what it costs

Closing curtains on sun-facing windows costs nothing. So does turning off lights and electrical equipment you're not using, which all give off heat, and checking your heating is properly off rather than sitting on a timer.

Moving to sleep in the coolest room in the house is free. And it may well be cooler outside in the shade than indoors, so sitting out isn't cheating.

If someone in your household relies on powered medical equipment, or on medicine that has to be kept in the fridge, the Priority Services Register is worth sorting out now. Heatwaves put strain on the grid and power cuts get more likely. It's free, every supplier has to offer it, and we made 37,967 referrals to it last year.

Worried about the bill?

If your energy bill was already a struggle before this hot spell, speak to us. We'll go through what's coming in, what's going out and which bills need paying first.

Most energy suppliers run hardship funds, and those are open all year rather than just in winter. We'll also check whether you're missing out on anything you're entitled to, because last year we found £70.6 million a year in unclaimed support for our customers. Try our benefit calculator.

And yu can find more useful information on energy here: What to do about energy arrears