Storage heaters Q.

[saveasteading]

Fe Iron

O  Oxygen

lite    ??? it is very heavy

 

Can you explain simply and approximately what these terms are compared to normal brick etc?

[SteamyTea]

  On 04/12/2022 at 16:57, saveasteading said:

Can you explain simply and approximately what these terms are compared to normal brick etc?

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Simply, yes, it is in the numbers.

 

Feolite has a SHC 0.92 kJ.kg^-1.K^-1, k 2.1 W.m^-1.K^-1 and rho 3900 kg.m^-3

 

Clay brick has a SHC of 0.8 kJ.kg^-1.K^-1, k of 1.3 W.m^-1.K^-1 and a rho of 1700 kg.m^-3

 

Thermal Inertia is calculated from the square root of the product of the above three

 

Feolite is 87 kJ.m^-2.K^-1.s^-0.5 

Brick is 42 kJ.m^-2.K^-1.s^-0.5

 

So basically, in the same amount of time, and at the same temperature differences, for the same exposed surface area, Feolite can release (or absorb) twice the amount of energy as ordinary clay brick.

But it has a mass of over twice that of clay brick.

So building a a house of out Feolite would not really make it more thermally stable, just heavier.

The reason it is used is it takes up less space.

Doing the same for pine and you get 371 kJ.m^-2.K^-1.s^-0.5 around 6 times the energy released.  Why the term 'thermal mass' is a nonsense term.

Though you would not want to stick an electrical element into a block of pine and heat it up.

 

Material properties from here:

https://material-properties.org/

[saveasteading]

  On 04/12/2022 at 17:33, SteamyTea said:

twice the amount of energy

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Twice as fast, or twice the total energy storage regardless of time?

 

Excuse me, covid does not allow consideration of equations.

[SteamyTea]

  On 04/12/2022 at 18:23, saveasteading said:

Twice as fast, or twice the total energy

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Twice the energy, in the same time, for the same area.

Or twice the power for the same area (power is J/s).

With heat transfer, area is important. Storage heaters take advantage of this by opening the flap and allowing more air to pass by. This is the same as increasing the area.

Edited December 4, 2022 by SteamyTea

[TonyT]

Dimplex quantum storage  heaters have digital controls so things have moved on from the input output dial. 
 

[zoothorn]

Do they do the fan thing on/ off overnight?? Just thought.. this would drive me insane, as badly having a storage heater in my bedroom doing this 11pm to 7 am, as I hear my awful ASHP doing something akin to this within-the-room fan intrusion in terms of noise from 3 bedrooms away. 

I bloomin hope I haven't made my folks sleep interrupted by these heaters.
 

 

[dpmiller]

the whole point of night-storage is that energy is being absorbed rather than released during this time so no, the fan shouldn't be running. The unit is trying to gain *internal* temperature so regardless of the external body temperature it's attempting to limit energy losses so flaps should be closed and fan should be off.

[TonyT]

Get a storage heater without the convector or keep this turned off as this is will run on the normal 24 hr electricity price and not the cheap off peak night time electricity 

[zoothorn]

  On 05/12/2022 at 08:02, TonyT said:

Get a storage heater without the convector or keep this turned off as this is will run on the normal 24 hr electricity price and not the cheap off peak night time electricity 

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Hi TT,

 

they don't have the means to change these two new expensive heaters now. They have frosted DG panes which they won't do be ause they can't afford to.. not in the sitroom or their bedroom tho.

 

So it's a question of trying to understand them ( I still can't.. so they've no hope in hell of then). I have an oil-filled rad here, which I spent hours on many calls to try understanding the digital display. Finally I did, but now cannot remember: so complicated, so I just use the big back switch to turn on & off. Often I forget it's on ( no obvious on light for eg) go out & waste money.

 

So trv's (was mine stuck? Was it meant to be like this? Could never get the answer- drove me insane), these stupid storage ones, my oil filled rad, & my ashp.. I cannot understand any of them. And I have a background in technical camera assisting, so, my 82/86 year old who struggle with tv remotes... haven't the slightest chance.

 

 

[zoothorn]

  On 05/12/2022 at 05:28, dpmiller said:

the whole point of night-storage is that energy is being absorbed rather than released during this time so no, the fan shouldn't be running. The unit is trying to gain *internal* temperature so regardless of the external body temperature it's attempting to limit energy losses so flaps should be closed and fan should be off.

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Hi dpm, unless I rip the thing apart & see how it works I just can't understand the 'flap' thing, or know it's relevance to this overnight excessive heat situation. And I can't visualise how a sheet of metal ( assuming a flap is such a design) can inhibit/ stop the heat emmitting. Especially if metal conducts heat well.

 

[saveasteading]

Could you leave the hrster on, with a simole timer in the socket?

[zoothorn]

  On 05/12/2022 at 14:16, saveasteading said:

Could you leave the hrster on, with a simole timer in the socket?

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That's a good plan, if the heater will allow this tho/ doesn't it need to be switched on 24/7 to do it's things?

 

[SteamyTea]

  On 05/12/2022 at 14:14, zoothorn said:

just can't understand the 'flap' thing

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It is really quite simple.

When the storage heater is charging up at night, the flap is automatically closed.

When it stops charging up, it opens to the pre set position.

The reason this works is because a storage heater is a convection heater i.e. air passes through it. All the flap does is limit, or stop the airflow.

Now don't tell me you cannot understand that.

Edited December 5, 2022 by SteamyTea

[saveasteading]

  On 05/12/2022 at 14:14, zoothorn said:

the 'flap' thing,

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I took some to bits to salvage the bricks.

It's such a simple, primitive thing.

Heater heats the blocks which are enclosed in a  box.

Lift flaps to release heat from blocks to air.

Hot air rises and draws room air in to be heated, and rise.

Close flaps and repeat.

 

If there was any insulation to contain the heat until wanted, I can't remember.

 

[SteamyTea]

  On 05/12/2022 at 16:36, saveasteading said:

If there was any insulation to contain the heat until wanted, I can't remember.

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There is a thin layer on the metal panels.

Probably asbestos wool on the really old ones from the 1960s.

  On 05/12/2022 at 16:36, saveasteading said:

It's such a simple, primitive thing

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Did you notice the small element on the the flap control to shut it down when charging?

[saveasteading]

  On 05/12/2022 at 17:17, SteamyTea said:

Did you notice

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No, it wasn't forensic standard. And it was due to  the skip in the  morning.

how does that work? 

[SteamyTea]

  On 05/12/2022 at 17:30, saveasteading said:

how does that work

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The flap is controlled by a bimetallic strip. Too hot, it closes, too cold, it opens. The output knob just mechanically limits the amour it can open.

On the bimetallic strip is a resistance heater that warms up when the E7 (or any power) is applied. This closes the flap and reduces losses when they are not needed (not so brilliant for really early risers like me, but lockout timers can easily sort that, or thick pyjamas).

Really simple and elegant solution to a problem. If it fails, the heater still works, just takes longer to heat up as losses to the room are higher.

 

[zoothorn]

  On 05/12/2022 at 16:24, SteamyTea said:

It is really quite simple.

When the storage heater is charging up at night, the flap is automatically closed.

When it stops charging up, it opens to the pre set position.

The reason this works is because a storage heater is a convection heater i.e. air passes through it. All the flap does is limit, or stop the airflow.

Now don't tell me you cannot understand that.

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ST I can only understand how a piece conductive of metal stops (excessive 5am charging heat) by becoming in an 'open' position.. if I see the thing doing it, or rip it apart.

 

Trying to explain like this, just words, when I'm still stuck on this bizarre excessively hot 5am situation & trying to fit some flap whatnot into the equation, which is closed by all accounts at 5am, then opens, but the thing is far less hot when it's open.. tbh makes bggr all sense to me. I haven't the feintest idea what's going on!

 

If the thing is logical, I will understand it. But if not.... it likely just won't click with me.
Superhot at 5am when you've turned it off.. is illogical.

 

 

[SteamyTea]

  On 05/12/2022 at 18:12, zoothorn said:

I can only understand how a piece conductive of metal stops (excessive 5am charging heat) by becoming in an 'open' position.. if I see the thing doing it, or rip it apart

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When I don't understand something that I read. I reread it until I do.

But if you still don't understand how something can be switched on and off, without pulling it apart, don't touch a light switch or a tap.

[saveasteading]

  On 05/12/2022 at 18:12, zoothorn said:

If the thing is logical, I will understand it. But if not.... it likely just won't click with me.

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Not necessarily. We understand different things. 

For me, electronics is magic.  Maths was ok until differentiation (passed but not understood)

 

But how a brick is hot in a box, then you let the heat out by opening the box sounds simple and logical to me.

 

So if you don't get it, it neither means that it is illogical nor that it is something to worry about: It needs someone who does.

[zoothorn]

  On 05/12/2022 at 18:36, saveasteading said:

Not necessarily. We understand different things. 

For me, electronics is magic.  Maths was ok until differentiation (passed but not understood)

 

But how a brick is hot in a box, then you let the heat out by opening the box sounds simple and logical to me.

 

So if you don't get it, it neither means that it is illogical nor that it is something to worry about: It needs someone who does.

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Ok now we're on a furrow I can cope with. Boxes with a hot brick in. 

 

Right. This is why it's illogical to me:
 

Ok you say the heat is simply let out when the box is open:- inferring that when it's closed, the heat isn't let out.

But at 5am the box is.. closed.. & letting so much heat out that its far hotter in fact, than at any time at all, when the flippin flap is open.... totally, opposingly, countering what you say right ^ here.

 

 

[dpmiller]

there's a small amount of energy at higher temperature coming through the outside of the box. You can feel this, yes. But this is very different to the large volumes of warmed air coming out when the flap is open. Temperature is not the same as heat energy, as no doubt @SteamyTea will once again try to explain...

[zoothorn]

  On 06/12/2022 at 07:01, dpmiller said:

there's a small amount of energy at higher temperature coming through the outside of the box. You can feel this, yes. But this is very different to the large volumes of warmed air coming out when the flap is open. Temperature is not the same as heat energy, as no doubt @SteamyTea will once again try to explain...

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Dpm, but it makes no difference to whoever's in the room exactly what process the heat they feel has been through... they feel heat, or not. They feel hot, or not.

 

There have been replies saying they'd never have one in a bedroom, that someone did once/ tried it on overnight/ never again, because, of the heat it emmitted in the small hours.

 

So these replies, & my finding the thing whacking out heat at 5am, don't chime with your saying "there's a small ammount of energy at higher temp coming thru outside of box" (assuming here you're referring to the small hours charge period). If Im sweating away in a hot room at 5am, I'm hot. If I'm hot, something has caused this. The radiator caused this.
 

To infer this is merely "a small ammount of energy released" cannot possibly be correct. Conversely in fact, a very large ammount of energy quite obviously, has been released instead.

Edited December 6, 2022 by zoothorn

[SteamyTea]

  On 06/12/2022 at 14:48, zoothorn said:

If Im sweating away in a hot room at 5am, I'm hot. If I'm hot, something has caused this. The radiator caused this.

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Have you tried sleeping with boxing gloves on.

[zoothorn]

  On 06/12/2022 at 14:50, SteamyTea said:

Have you tried sleeping with boxing gloves on.

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Yes. My hands got hot. I knew the cause of the heat in just my hands, because when I woke up, I was wearing boxing gloves.