Economy 7 Storage Heaters

How Economy 7 works

Cheaper electricity for about 7 hours a night. Economy 7 gives you a lower price for roughly 7 hours overnight. The exact times depend on your meter and supplier. Many homes get midnight to 7am, but yours may be different.

The heaters charge up overnight. Bricks inside the heater soak up heat at the cheap night price.

They give the heat out the next day. The stored heat comes out slowly through the day. By late evening most of it has gone. That's normal.

Anything used in the day costs the full day rate. That includes the boost or convector panel on the front of some heaters.

The two dials on most storage heaters

• INPUT (or "charge"): how much heat to store tonight. Turn it up when tomorrow will be cold and down on milder days. On newer heaters, like the Dimplex Quantum, you set it once and the heater works it out itself.
• OUTPUT (or "boost"): how fast the heat comes out. Keep it low or off overnight and in the morning so the heat lasts. Open it up in the afternoon and evening when you need it.

Got a Dimplex Duo Heat? Dimplex don't make these any more, but there are still lots of them in homes. I've got a step-by-step set-up video and a fault code guide here

If your Duo Heat has developed a fault, it may be time to replace it rather than repair it. Get in touch and I'll talk you through the options.

What switches your heaters on at night?

Every home is different. Have a look near your meter and see which of these you have. Many homes have more than one. Please just look. The meter, timers and seals belong to your energy supplier, so don't open them.

E7 timer clock. An old-style clock that switches the heater circuit on at night. It belongs to your energy supplier and is set up when it's fitted, so there are no settings for you to change. Please don't touch it.

Old two-rate meter. Two sets of numbers: one for the cheap night rate (LOW) and one for the day rate (NORMAL).

Heating contactor. A heavy-duty switch. The meter sends it a small signal and it switches the big heater circuit on.

Smart meter. Smart meters look the same whether or not they're set up for Economy 7. Your supplier switches the night rate on remotely, so check your bill to be sure.

Radio teleswitch. An older box next to the meter, with the words "Radio Teleswitch" on the front. A radio signal from your supplier switches it on at night. These are being phased out, so if you still have one, ask your supplier about changing it for a smart meter.

Changed energy supplier? Check this first

Changed supplier since you last used your heaters?

Your new supplier may not be sending the night signal that turns your heaters on. Check that your bill says Economy 7 (or a night or off-peak rate). If it doesn't, or you're not sure, call the company you pay and ask them to check your meter and your tariff. Their number is on your bill.

Power cut? Call 105. It's free, 24/7, anywhere in the UK.

Turning them back on after the summer? Go gently

This one catches people out every year. Dust settles inside the heater over the summer. If you switch it straight to full power, that dust can overheat and trip the heater's overheat safety cut-out. It works for one night, then stops.

Night 1: lowest setting.

Night 2: halfway.

Night 3: wherever you like it.

That burns the dust off slowly and saves you a call-out.

Hot water on Economy 7

Your hot water cylinder usually heats up overnight on the cheap rate too. If your water is only lukewarm, it's often because only the boost is being used, and the boost just heats the top of the tank. I explain it properly on my immersion heater page.

Good habits

• Never cover the heater. No washing, towels or furniture against the vents. Covering it can also trip the cut-out.
• Hoover the vents once a year, with the heater switched off and cold.
• Leave the meter and its boxes alone. Just look and match them to the photos above.

Free download: Economy 7 help sheet

Everything on this page on a 3-page printable sheet, with photos and the customer service numbers for the main UK energy suppliers. Keep it next to your heaters.

Still cold? Book a video call with Karl

Wherever you are in the UK, you can book a 30-minute video call with me for £45 + VAT. Show me your heaters, meter and controls on your phone and we'll work through your set-up together. I can't promise a fix over video, but most of the time we get to the bottom of it, and if it does need an electrician, you'll know exactly what to ask for.

Need a repair or a new heater?

If you're local to Loughton, Debden, Buckhurst Hill, Chigwell, Woodford or Chingford, I can come out to you. Have a look at our storage heater repair and replacement page, or get in touch.

Economy 7 questions I get asked a lot

Why is my storage heater cold in the evening?

That's normal for older heaters. They store heat overnight and let it out through the day, so by the evening most of it has gone. Keep the OUTPUT low in the morning so more heat is left for later.

My heater worked for one night after the summer, then stopped. Why?

Usually it's dust. It overheats on the first full-power night and trips the overheat safety cut-out. Start on a low setting for the first couple of nights next time. If it's already tripped, book a video call or get an electrician to look at it.

I've changed supplier and my heaters aren't charging. What's wrong?

Your new supplier might not have your meter set up for Economy 7, so the night signal isn't being sent. Check your bill says Economy 7 or off-peak, then call your supplier.

Can I tell if my smart meter is set up for Economy 7?

Not by looking at it. They look the same either way. Your bill will tell you, or your supplier can check.

Why is my hot water only lukewarm on Economy 7?

Usually it's been heated on the boost only. The boost just heats the top of the tank, so once it's off, cold water from the bottom mixes in. Leave the night-rate immersion switched on so the whole tank heats overnight.

Is the boost button expensive to use?

Yes. The boost or convector panel uses day-rate electricity, so use it sparingly.