The ultimate five tricks energy experts use to keep heating costs down, including how to HALF your bill

You may think you’ve tried every trick in the book to keep your energy bills low and your home nice and warm when the temperature outside drops.

But even if you’ve already insulated the attic and blocked out all drafts, there are still things you can do to make your home more energy efficient.

Money Mail talks to hands-on experts, from gas engineers to builders, for their practical tips you might not have considered.

Check the pressure gauge of your boiler

Dom Roque, general manager of Dom’s Heating and Plumbing, recommends a few basic checks you can do on your heating system to ensure it’s in good working order.

And an annual service by a professional, which usually costs around £100, will be money well spent.

‘An annual check helps spot problems – such as leaks and worn parts – before the boiler breaks on Christmas Eve and you need an emergency call costing hundreds of pounds,’ he says.

If you want to do some simple checks yourself, the first step is to look at the pressure gauge on your boiler, says Dom.

A modern pressurized boiler heating system will typically indicate between one and two bars when the boiler is on. If it is lower, there may be a leak.

The gauge is normally located on the outside of the boiler, on the front of the device – a round dial the size of a small stopwatch.

Look at this gauge and if it reads between zero and one, place your ear against the boiler without touching anything and see if you hear a slight hissing sound, which indicates that steam or water is escaping from the system.

If you hear this, there may be a malfunction in a relief valve on the unit that needs to be replaced by a gas technician.

Also listen for a hissing sound from your radiators to check if water or steam is escaping from them.

If this is the case, you may be able to resolve this yourself. At the top of each radiator there should be a small valve with a square tap that can be tightened or loosened with a radiator wrench. These can be purchased at a hardware store for about €2. If you hear a hissing sound, you can turn it clockwise until it stops – and is closed.

Don’t forget the hot water tank

If you have a separate hot water tank in the dryer, check whether there is an expansion tank connected to it that needs to be repressurized.

This is a balloon-sized metal cylinder that usually sits above or next to the hot water tank.

It also acts as a relief valve. It contains both air and water and takes in extra water as the tank and central heating system heats up and the water expands – and releases it as it cools.

If it is not working properly, it may be full of water. The only way for the excess water to escape is through an overflow pipe connected from the boiler to the outside of the house. You can identify the pipe outside your home to see if it is dripping.

Details of the required pressure for the expansion vessel should be clearly indicated on the side of the unit. If you have a modern bicycle pump with a pressure gauge, you may be able to re-inflate the barrel to the required pressure level – but in most cases it is best to leave this to the professionals.

Do the radiators have cold spots?

If your radiators are not heating up as usual and there may be cold spots at the bottom, this indicates that there may be sludge in them. Once this is resolved, your heating bill could be halved.

It can be a messy job if you try to sort it out yourself, so it’s best to leave it to a qualified boiler expert who has the equipment needed to clean the radiators with a power flush. The equipment can be located outside the house.

Dom says: ‘If your radiators are full of sludge they are half as efficient – ​​it’s like boiling a pot of fresh water instead of a pot of mud. The latter can double heating costs.’

An occasional ‘power flush’ of your radiator system by a plumber will cost around £300, but Dom says it will pay for itself within a year.

He adds that air in radiators can cause rust, so bleed them every year. You may be able to do this yourself. If you’re not sure, you can find practical guidance on YouTube.

Is there too much attic insulation?

Builder Mike Edwards, 68, who started out as an apprentice bricklayer more than half a century ago, fears too many homes are filling every hole in their attic with insulation – a costly mistake.

The co-founder of the website DIY Doctor says: ‘There is a misguided belief that an attic full of insulation keeps bills down, when the opposite could be true.

The roof space should be cool and drafty. Otherwise, the warm air hitting the cold roof will cause condensation to form, causing the wooden beams to rot and the insulation to become damp.’

Mike suggests that the insulation should be 270mm thick, but not pressed down tightly. If it is installed under planks in the attic there should also be a 50mm air space between the insulation and the planks.

You should leave a gap of at least 25mm between the insulation and the eaves – the part of the roof that overhangs the wall of a house. About 25 percent of heat is lost through an uninsulated roof, so if done correctly it will save you at least $300 a year.

Place a jacket on a heating element

This cylinder in the dryer is rarely understood or used efficiently to keep energy bills low, Dom believes.

He says: ‘Think of it as a giant kettle – with an electric heating element in it.’

There is no need to leave the heating element on all the time if you don’t need hot water all day as this can cost more money.

If you turn it on just an hour before you need the hot water, this is plenty of time for it to warm up.

Dom says the cylinder should be well insulated: wrap it in a £20 jacket and make sure any connected pipes are also covered.

This costs €1 per meter of insulation and should save at least €50 per year on your heating bill.

Look up the manual and make sure the settings provide heat when you need it.

You don’t have to leave it on when you are away for a day (for example at work) or on holiday.

toby.walne@dailymail.co.uk