Dimplex Storage Heater

[rich_d8]

This is probably going to sound really stupid, but i have just moved into a flat with 2 dimplex storage heater (Model number CXL24N) and i was just wondering how they work.

I understand that they only come on overnight as they are connected to a different circuit but do they stay on full the full 7 hours of economy 7 or do they turn off when they are fully charged ?

I am trying to estimate how much it is going to cost me to use them. Does anyone else have Dimplex storage heaters and knows for example how many hours are needed to reach full charge, medium or low charge.

Any help is greatly appreciated.

[961]

Originally Posted by rich_d8

This is probably going to sound really stupid, but i have just moved into a flat with 2 dimplex storage heater (Model number CXL24N) and i was just wondering how they work.

I understand that they only come on overnight as they are connected to a different circuit but do they stay on full the full 7 hours of economy 7 or do they turn off when they are fully charged ?

I am trying to estimate how much it is going to cost me to use them. Does anyone else have Dimplex storage heaters and knows for example how many hours are needed to reach full charge, medium or low charge.

Any help is greatly appreciated.

Storage heaters rely on the fact that some electricity tariffs charge lower rates at certain times in the day

If you contact the electricity company that supplies the juice for your flat they will tell you the tariff that you will currently be charged. You may find cheaper by using a comparison site.

Basically, most "economy 7" or "dual tariff" electricity prices provide a daytime rate and a reduced price nightime rate. The lower rate operates, usually, for 7 or 8 hours overnight and is usually around half the price of daytime. Storage heaters use this reduced price electricity by charging at night and gradually releasing the heat during the day to provide heat over 24 hours

A storage heater is basically a pile of heavy bricks surrounded by elements like those in a cooker grill and high quality insulation. When the time switch turns them on, the elements get hot and warm the bricks to very hot. The insulation keeps the heat in the bricks and the whole thing gets warm and releases heat during the day

A variety of controls allows you to adjust the amount of electricity going in and control the heat coming out. In periods when it is cool rather than cold, you can set the input at low. When it's brass monkeys outside, you can turn the input up to max

If you are out all day you can usually close a regulator to slow the rate that heat escapes allowing you to open the regulator later in the day when you want the heat

Some electricty suppliers arrange for a "boost" or further charge, later in the day, so that evening performance is better

Storage heaters are a good idea if your flat is well insulated and you do not have an open fire, which extracts heat as the air is drawn up the chimney

To answer the specific question you ask, they will stay "on", drawing charge, for the full period of the reduced period electricity (you can probably see what this is by looking at the time clock where the electric meter is), but they will cycle on and off, like an electric cooker thermostat works, according to the setting of the input dial that you control. These are usually 1 to 6. 1 will give barely warm (inexpensive) and 6 will be s..t hot (bit more, but still probably ok)

The dimplex web site will give you information about the specific models you have

Incidentally it is usually the case that any other electricity use such as immersion heater for hot water as well as the washing machine and other high energy items will benefit from this cheaper electricity which can extend in some areas to 8am gmt

[rich_d8]

Thanks very much for the quick response.

My economy 7 is active from midnight to 7 in the morning. and my night rate is 3.9p.

Does that mean that the heater will be using full power for the full 7 hours?

If that is the case, it will look like this:


My storage heaters are 3.4kwh.

That equals 3.4kwh x 7 hours x 30 days (for the month) = 714 Kwh

= £27 a month Per heater



Or will it reach full power, and then the therostat will kick in and maintain that temperature the econmy 7 turns off. If that is the case the heater wont be consuming the full 3.4 Kwh per hour.

Is that correct or not?

[961]

Originally Posted by rich_d8

Thanks very much for the quick response.

My economy 7 is active from midnight to 7 in the morning. and my night rate is 3.9p.

Does that mean that the heater will be using full power for the full 7 hours?

If that is the case, it will look like this:


My storage heaters are 3.4kwh.

That equals 3.4kwh x 7 hours x 30 days (for the month) = 714 Kwh

= £27 a month Per heater



Or will it reach full power, and then the therostat will kick in and maintain that temperature the econmy 7 turns off. If that is the case the heater wont be consuming the full 3.4 Kwh per hour.

Is that correct or not?

The heaters will never consume the full 3.4 kw per hour over the full period

When they switch on, the elements will consume 3.4kw per hour until they reach their operating temperature (no more than two or three minutes), at which point they will cycle on and off until the internal temperature of the bricks reach the temperature set by the input dial. At this point the elements will cycle on and off merely to maintain that temperature until the time switch turns the unit off

When the input dial is set to the lowest setting the cost will be minimal

The way to establish the true cost of heating using these is to take a reading of the night dial of the meter (or the central heating dial if you have a third dial in your meter) and then a second reading of the dial in the morning after the circuit has switched off

Do this over a week until you have established where you need to set the input dials and then establish the units used x 3.9p plus vat

A properly designed storage heater system can be economic and no more expensive than other methods, particularly if the night rate is used to heat hot water in a properly insulated tank. In the depths of winter some additional heat may be required late evenings

Don't rip them out until you find out how much they really cost

[rich_d8]

Originally Posted by 961

A properly designed storage heater system can be economic and no more expensive than other methods, particularly if the night rate is used to heat hot water in a properly insulated tank. In the depths of winter some additional heat may be required late evenings

Don't rip them out until you find out how much they really cost

I think the flat has been set up very badly as it has a fortic combination tank and also an electric shower. Therefore i am heating the water over night and not actually using it for the shower as it is heating the water through the electric shower. (i assume)

Is there a way to bypass the electric shower and use the water that was heated overnight for the shower without replacing the tank?

Excuse my ignorance, i really know nothing about this subject.

[961]

Originally Posted by rich_d8

I think the flat has been set up very badly as it has a fortic combination tank and also an electric shower. Therefore i am heating the water over night and not actually using it for the shower as it is heating the water through the electric shower. (i assume)

Is there a way to bypass the electric shower and use the water that was heated overnight for the shower without replacing the tank?

Excuse my ignorance, i really know nothing about this subject.

Not worth the cost quite frankly

Only way round is to shower in the cheap electric period

[DPinBucks]

Personally, I don't think it's all that bad a system for a flat.

For showers, you'd need a big hot water tank to be sure you've got enough to last all day, assuming it's only heated by Economy 7. If it's topped up during the day then you'd gain nothing over an electric shower.

Assuming your shower is rated at 10kW, then a 10-minute session would use 1 kWh, costing about 12p at full rate or 3.9p on Economy 7. With the latter, say 2 showers a day would save you about £60 a year. Not peanuts, but not worth the cost of tearing out your plumbing & starting over.

[rich_d8]

Originally Posted by DPinBucks

Personally, I don't think it's all that bad a system for a flat.

For showers, you'd need a big hot water tank to be sure you've got enough to last all day, assuming it's only heated by Economy 7. If it's topped up during the day then you'd gain nothing over an electric shower.

Assuming your shower is rated at 10kW, then a 10-minute session would use 1 kWh, costing about 12p at full rate or 3.9p on Economy 7. With the latter, say 2 showers a day would save you about £60 a year. Not peanuts, but not worth the cost of tearing out your plumbing & starting over.

I see what your saying, but nothing else in the flat is using hot water, therefore i am heating the whole tank overnight for a little bit of hot water to maybe wash my hands with. aswell as this i am also paying for the hot water in the shower. So paying to heat the water twice, seems a little silly, when the tank could do it all. I live in a one bedroom flat with my girlfriend, surely water heated up overnight would be sufficient for a few showers a day.

[rich_d8]

Do you know what kind of a setup i would need and the costs that would be incurred if i did want to switch?

Thanks

[961]

Originally Posted by rich_d8

Do you know what kind of a setup i would need and the costs that would be incurred if i did want to switch?

Thanks

If you don't use the water in the tank why not disable the overnight heating of that and just go with the 12/15p cost of a shower?

If the tank is well insulated, and you are not using much water out of it, I think the cost of heating it will not be worth bothering about

I honestly feel it's worth leaving things as they are until you find the costs are too much. You may well find things are ok

[DPinBucks]

If the hot supply is only for washing/-up, then the tank isn't going to be very large. As 961 says, the cost of reheating it overnight won't be much.

An electric shower heating water on demand is easily the most efficient way of using energy, because none is wasted. If you think about it, you're proposing to use electricity for shower water in exactly the same way as you're now worried about its use for water for washing, but on a much larger scale.

For a small flat, I cannot see that any other system than you've got would be more cost-effective. You say " a few showers a day". Even if you mean only two each, then you'll need a large tank heated by Economy 7 overnight. There's probably not enough room in the flat. Also, you might want to check the terms of your lease (I take it it's leasehold?). You're probably not allowed to make that sort of change.

Be all that as it may, I can't see you making the changes you want at much under £500:

• New tank;
• New shower;
• Installation & plumbing

[DPinBucks]

A further thought:

How exactly is your electricity supplied? Are you on a single supply which drops to the cheap rate overnight, or are there two supplies and two meters?

Either way, your hot water will be kept topped-up by an immersion heater, with a timer which you can control. It wouldn't be possible to rely simply on overnight heating for hot water all day. Don't forget the flat has been designed for a variety of possible occupants, including a mother and baby or possibly elderly people who would want hot water all day. What do you do for clothes washing, for example?

If you're both at work, I suggest you buy a timer switch (if there isn't one already) with two time settings per day, to heat your washing water for when you get up and when you get home.

[Super Andy H]

I had Economy 7 heating in my flat. This was about 5 years ago. I had it set to about half way. My electric bill was £15 a month. So I wouldn't worry.

I now have a 3 bed detached bungalow. My gas and electricity combined bill is £150 a month. Oh how I miss the flat.


And you should have 2 meters for the flat. One for "normal" electricity use, and one for economy seven.

[rich_d8]

Thanks for the advice.

I do have 2 meters, well technically its one meter with 2 readings and a teleswitch to change over rates.

Maybe im being really stupid and missing the point, but i still dont believe that it can be cheaper to heat a water tank every night on economy 7 (only to use a very small ammount of that water) and still pay for the shower to heat the water aswell.

I should point out that i have a dishwasher and washing machine, both of which have a cold water feed.

Therefore the water in the tank wont really get used and will keep on getting reheated at night. Maybe this is going to be cheaper than i expect as the immersion will only maintain the tmeperature and not have to heat it from cold.

I have checked the lease and am allound to use the loft space if i want to. Do you really think the setup i have will be cheaper to run than any other method?

Maybe i am missing the point here!!

If so please feel free to point it put

[961]

Originally Posted by rich_d8

I do have 2 meters, well technically its one meter with 2 readings and a teleswitch to change over rates.

i still dont believe that it can be cheaper to heat a water tank every night on economy 7 (only to use a very small ammount of that water) and still pay for the shower to heat the water aswell.

I should point out that i have a dishwasher and washing machine, both of which have a cold water feed.

Do you really think the setup i have will be cheaper to run than any other method?

Well, time will tell.But in the meanwhile the real place you can economise on electricity with your setup is to ensure that the washing machine and dishwasher are controlled by timeswitches so that they operate during the off peak period. Heating water from cold in the machines costs a bomb if done on daytime rates. An alternative is to change the feed if possible so that the machines use hot water feeds from the hot water system

As has been said you will not benefit by changing the power shower

Ensure the water heating is done on a timeswitch. We heat water for a three bedroom house by immersion heater which is timeswitched to operate only for 90 minutes just before the cheap rate ends.

Ensure you know if the change from night to day rate on the meter moves by an hour or not when summer time ends