Storage heaters Q.

[zoothorn]

Hi Chaps,

 

I seem to have a similar confusion as before with these damn heaters. Not mine, my parents. I just cannot understand them.

 

Ok my very old parents moved to a house 6 years ago, having old brown 80's storage heaters in. I noticed at 5am one (main livingroom) was on, extremely hot at 5am. So, I think I asked on here at the time wtf? Etc. The consensus was, I recall that it had likely stuck open, or at the least it wasn't correct/ was faulty. So it was replaced, £700 or so, 18 months ago.

 

Now, the last time I stayed, april, this new storage heater was on, as far as I could tell producing tepid heat during the evening (fairly uselessly imho) & the ruddy fan going on/ off slightly irritatingly.. also suggesting the thing was working as normal I might assume during the evening. But again I come down at 5am.... & the damn thing is belting out heat, extremely hot. Just like the old one. 

 

This whole thing makes no logical sense. Can anyone shed any light?

 

Thanks, zoot 

 

 

[TonyT]

Dials on the storage heater for input and output.

 

input how much charge goes in

output - how much heat comes out.

 

higher input - cost more 

generally check weather the day before and adjust input to suit weather.

 

normally on an off peak /E7 tariff, charging at night on cheaper electricity 

 

storage heaters with one cable is a plain storage heater

 

storage heaters with 2 cables also have a convector fan heater that can run anytime if the day- on normal or higher rate electricity

[ProDave]

Storage heaters charge up with heat from usually 7 hours of cheap rate electricity from roughhy midnight to 7AM, so at 5AM they will have been charging for 5 hours so the brick core will be close to it's maximum temperature by then.  No surprise it feels very hot.  The trick is to keep the "output" control down as low as possible as long as possible to keep the heat in as much as possible and then turn the output control up in the evening to let the remaining heat out quicker.  Some try and automate this a bit with crude bimetailic mechanism.

 

If you changed them just a few years ago they won't be the bomb proof simple old type, but something more complicated with electronic controls and a permanent supply as well as the off peak supply.  These tend to concentrate on maintaining a constant temperature, using peak rate electricity to make up any short fall in stored heat.  I would not personally choose that type, I would have kept the old one.  Most bits of the old ones can be fixed or replaced.

[zoothorn]

So this new one isn't faulty then-? Which means the old one, which I persuaded them to change ( because it was 'stuck on' at 5am.. this was the consensus, I hadn't heard of any heater 'sticking on', via some flap mechanism, but this was the consensus)... wasn't likely at fault then at all.

 

These drive me insane. I can understand they charge at night & store. Then release the stored charge evenly during the evening for eg. Makes logical sense, due to cost aspects. But if you have one say in a bedroom, you had it on evenly for hours in evening for eg, setting to to go off at say 11pm ( this seems just normal)... I dont want, or either expect it, to be belting out heat at about 10x the rate it did during the evening... at 5am!! This is preposterous. 1) as an utter waste of heat, 2) at the very time it's not needed, 3) making a bedroom uncomfortably hot possibly waking you up ( would me).. then you're 3) annoyed at this situation how irritated at 5am ( so getting back to sleep not easy), and 4) you're stressed because the only logic it's on maximum heat like this... is that it's faulty. Preposterous.

 

 

[zoothorn]

Thanks TT & ProDave for the replies btw, I trust you are keeping well. I'll dive in about the intricacies of how they work from your replies.. but it was just this  one 5 am thing I was asking about ( ie is it, or is it not... faulty). I cant cope with too much info on any of these wretched heating systems.... be it, trv's, my ASHP ( the most insanely annoying unfathomable thing even for Vaillant engineers here to understand), now these wretched storage heaters, all are unfathomable to me. 

 

Im now off to make a fire on a tiny stove a fraction the cost of these systems.. & get warm. Uncomplicated. Simple. And free too.

 

Zoot.

[Susie]

You most likely do not have a faulty heater. 
I live in Cornwall our economy 7 hours  are 12 to 1 and 2 to 8. All areas are different so check with your electric supplier. 
The storage heaters are timed to start charging up at 2 by 8 and  I suspect a lot earlier they are fully charged up. By that I mean the storage bricks have soaked up as much heat as possible to be dispersed slowly throughout the day. The old beige ones had a flap at the top in the grill bit when you adjust the output it opens the flap a bit more for each number so 1 is a bit open and 10 fully open this allows the heat out quicker. Note it’s all mechanical at the end of the day if you don’t move dial back to 1 the flap is still open so at 5 o’clock as well as still charging if you didn’t close the flap it is also releasing all that stored heat back out. It took my mum a while to get this. 
for your parents get them to sit down and look through the grill near the top as you adjust the output and they will see the flap move. 
The new one will be similar in that by the last hour of your economy 7 hours it will be very hot and the heat will be released in timed periods depending on a schedule. It’s most likely still a flap but for example it will open at 8 for few hours then close, open again at 1 till 3 when it closes and opens again at 5 till 10. They can be programmed to release the heat very slowly all day or nothing till the evening. 
The old ones are most likely on their own circuit linked in to a time clock at the meter. We are on 3 phase and economy 7 getting the time on an old radio wave clock if your on the same you may hear a clunk as the circuits are switched on and off eg for me 12, 1, 2 and 8. If you have a smart meter you are definitely not on the old radio wave time signal. 
Im sorry you replaced one it was unlikely to be broken if they do break it’s the opposite not heating up at all. 
if I can help mor ask away and post a picture and we can try to help. 
 

[ProDave]

Storage heaters are far from perfect, in fact a lot of people describe them as utter rubbish (sometimes using rude words)  But in a house with no mains gas, they are often the cheapest option, or were.  They work better in an office where they only have to deliver heat until 5PM and nobody cares if they are stone cold in the evening.  They also work better on Economy 10 which has it's 10 hours of cheap rate spread at 3 different times of day so they don't have to keep heat stored in for as long.

 

The flap that opens to let the heat out is controlled by the output control.  There is usually a bi metalic strip mechanism that attempts to give it some control so the more the core temperature falls the more the flap opens to let the heat out quicker.  There is also a crude mechanism that is supposed to close the flap whenever the heater is receiving a charge, perhaps that mechanism was faulty on yours?  But really that mechanism is only there for people who forget to turn the output control back to zero when they go to bed.

 

The modern one that uses a fan to circulate the heat would probably annoy me if the fan was not silent.  Nothing you can do about that one now.

 

The only alternatives in a house without gas are an Air Source Heat Pump and I suspect you might not be advising that, or oil fired boiler.

 

 

[zoothorn]

@Susie Hi there, very grateful for your reply. I'll be diving in to these detailed replies, best I do so with the thing in front of me/ at xmas when I visit. It's difficult to fully understand now.

 

Again I can under their overnight charging principle, but the excessive heat at 5am, seems peculiar. From yours & ProDave's replies, if its the bricks that charge/ soak up the heat, getting to maximum saturation let's call it at 5 am.. then why at 7am are they back to an 'off' situation? How (&where) does this heat become hidden then, if they don't feel warm during the day, until the heat is 'released' when the timer says 'on' at 6pm?
 

And my understanding of why any heater would be designed to be excessively hot at the very time it's not wanted, still seems not just bizarre, but completely ridiculous, & totally wasteful; & I just can't see why anyone would deem this a worthy design.

 

I'm kicking myself terribly though, as I persuaded them to replace two large ones ( because it was deemed they were faulty & 'flap stuck open' being flat-out hot at 5am). They're hard up, have no luxuries in life ever, & I persuaded them unnecessarily by all accounts, to spend 2x£700. I feel awful about this. Totally my fault.

 

zoot

 

 

 

[zoothorn]

19 hours ago, ProDave said:

Storage heaters are far from perfect, in fact a lot of people describe them as utter rubbish (sometimes using rude words)  But in a house with no mains gas, they are often the cheapest option, or were.  They work better in an office where they only have to deliver heat until 5PM and nobody cares if they are stone cold in the evening.  They also work better on Economy 10 which has it's 10 hours of cheap rate spread at 3 different times of day so they don't have to keep heat stored in for as long.

 

The flap that opens to let the heat out is controlled by the output control.  There is usually a bi metalic strip mechanism that attempts to give it some control so the more the core temperature falls the more the flap opens to let the heat out quicker.  There is also a crude mechanism that is supposed to close the flap whenever the heater is receiving a charge, perhaps that mechanism was faulty on yours?  But really that mechanism is only there for people who forget to turn the output control back to zero when they go to bed.

 

The modern one that uses a fan to circulate the heat would probably annoy me if the fan was not silent.  Nothing you can do about that one now.

 

The only alternatives in a house without gas are an Air Source Heat Pump and I suspect you might not be advising that, or oil fired boiler.

 

 

Hi ProDave,

 

do you mean better fir an office, because the newly-charged heater at 5am... will work more effectively, if it releases this heat, as soon as possible? Or rather sooner ( during the day) rather than storing all day to less,-effectively release it 6pm-11pm?
 

Ive noticed this new one you see, although I up the temp ( as soon as I visit without them looking) to 23*C, the room remains only tepid/ never warm at all. And yes spot on: the fan is not something I could live with too: it's on/ off/ on regular thing is similar to my dreaded ASHP 11pm-7am going on/ off/ on infuriatingly ( but nothing like as intrusive-sounding, not remotely close). It's background-irritating that's all. But they had no idea any audible fan would be present in any storage heater replacement. Nor would I have. I'd be furious. My dear old folks.. just put up with it, blankets on legs & waterbottles to keep warm because the thing's innefective at their 20*C setting & the room's not warm, & put up with my insisting they spend £1400 on them too. 
 

So I'll be pampering them this xmas to make up for my terrible mistake.. it's all I can do. 
 

Thanks, zoot
 

 

 

[ProDave]

When I moved into my 1930's semi 35 years ago, it had storage heaters and an open coal fire.  In that first winter I would get home from work to a cold house, even with the storage heaters on max, and then light the open fire.  I later upgraded to a gas fire (LPG bottles) but at least it was instant heat.

 

I have a theory that storage heaters tend to let the heat out quite high up, and with a poorly insulated house (no floor insulation) even if the rest of the room gets warm, there is a pool of cold air at floor level that never gets warmed properly.  Fitting under floor heating in our last house was a revalation, no more pool of cold air at floor level.

[zoothorn]

5 minutes ago, ProDave said:

When I moved into my 1930's semi 35 years ago, it had storage heaters and an open coal fire.  In that first winter I would get home from work to a cold house, even with the storage heaters on max, and then light the open fire.  I later upgraded to a gas fire (LPG bottles) but at least it was instant heat.

 

I have a theory that storage heaters tend to let the heat out quite high up, and with a poorly insulated house (no floor insulation) even if the rest of the room gets warm, there is a pool of cold air at floor level that never gets warmed properly.  Fitting under floor heating in our last house was a revalation, no more pool of cold air at floor level.

Food for thought there ProDave. At least my folks home is adequately insulated, if not VG, it's a semi-detatched so that helps. They do have a fireplace 'hole' with an electric bar fire in front on it (they dont use as too costly).. which mice were getting into livingroom from. So I've temporarily blocked with a ply board & foil front ( in case they do put fire on) & told thdm "please leave a gap fire to board". But ideally I need to ask on here about a better/ proper block panel, as cold no doubt gets in through my ply.
 

Your reply here describes my livingroom better, & food for thought on undertaking some project to redo it's whole floor: no insulation, permenant cold 'up to knees' level even with my stove flat out for 2 hours. Unbearable tbh.

 

But not to go off track. I'll try tempting them to run the heater earlier in day maybe. But they're so pennypinching even before this energy crisis, so it will be a fruitless task.

 

Thanks, Zoot

[SteamyTea]

3 hours ago, zoothorn said:

And my understanding of why any heater would be designed to be excessively hot at the very time it's not wanted, still seems not just bizarre, but completely ridiculous, & totally wasteful; & I just can't see why anyone would deem this a worthy design.

Look up Newton's Law of cooling, it is not linear.  So to get usable thermal energy delivery later in the day, the stating temperature has to be high.

The timing is nothing to do with the storage heaters, it is the time that the National Grid had deemed the most useful to them, and the power generators, to deliver cheap power.

 

They can always have a heat pump fitted, I am sure they are eligible for a free one.

Edited December 3, 2022 by SteamyTea

[TonyT]

https://www.cse.org.uk/advice/advice-and-support/night-storage-heaters
 

 

some easy to understand info

[Gill]

16 hours ago, ProDave said:

 

I have a theory that storage heaters tend to let the heat out quite high up, and with a poorly insulated house (no floor insulation) even if the rest of the room gets warm, there is a pool of cold air at floor level that never gets warmed properly.  Fitting under floor heating in our last house was a revalation, no more pool of cold air at floor level.

 

Very much my current experience.  We recently had underfloor insulation but still a noticeable cold pool of air at ground level. I have a suspicion that once we've replaced windows and added CWI, this will still be an issue that won't be solved by high retention storage heaters or moving to oversized rads /ASHP. 

[Gill]

@zoothorn I should add that the underfloor insulation has made a noticeable difference to the heat loss so if that's something your folks don't yet have it's worth looking into.  Hopefully funding / grants available.  Unfortunately my experience with our storage heaters is the same as yours.  Old style, controls set to full charge overnight and minimum release - by evening they are releasing very little warmth & nothing near what would be required to heat the room.  Doesn't help that mine are positioned on uninsulated external wall next to leaky window.  

[ProDave]

As to why 5AM seems to be the hottest time.

 

They start charging with heat about midnight, give or take a bit depending on where you are.  They charge until the core has reached the required temperature as set by the input control.  It is unlikely they will take the full 7 hours to fully charge, so about 5PM would be a likely time to reach peak temperature and then just maintain that until the E7 time finishes about 7AM.

 

Of course a better control system would be to calculate the expected heat loss in the house in the next 24 hours, and from that calculate how much charge the heater needs, and adjust the start time so it finishes charging just as the off peak time finishes.  That is boffin territory but at least one well known member here has a control system that does that calculation each night and does just that, adjusts the start time according to how much charge is needed. 

 

A simpler version would be just make the "input" knob adjust the start charge time, so at maximum it would start at midnight, at minimum it might not start until 5AM and then it would charge until the off peak time ends.  I doubt even the new posh electronic ones even do anything as useful as that.

[SteamyTea]

45 minutes ago, ProDave said:

A simpler version would be just make the "input" knob adjust the start charge time, so at maximum it would start at midnight, at minimum it might not start until 5AM and then it would charge until the off peak time ends. 

Basically what @TerryE does automatically, and I do manually on my timers.

 

Blue Columns

 

Edited December 4, 2022 by SteamyTea

[saveasteading]

3 minutes ago, ProDave said:

storage heaters tend to let the heat out quite high up,

Yes this is how it will work: a stream of hot rising air, but too slow to cause general movement round the room.

When putting the angel on the tree it is so much hotter up there.

 

All hot air rises, and it can be extreme in a warehouse situation. 10m up on a cherrypicker it can be very hot unless the air can be brought down again. These fans exist but are underused, 

 

Back to domestic: Hence continental room fans have a reverse switch. Downwards in summer because the draught itself is what causes the cooling feeling, but up in winter to force the warmer air down where useful.

[zoothorn]

15 hours ago, TonyT said:

https://www.cse.org.uk/advice/advice-and-support/night-storage-heaters
 

 

some easy to understand info

Hi TT, appreciate this.

 

Actually all this I understand. How the thing stores overnight/ releases/ how typical dials work (actually this is still not fathomable to me, let alone my 82/86 yr old folks.. but this aspect isn't in question for now, for this thread).

 

But it omits information on the very aspect I do not understand. The extremely hot rads, at 5am. So the whole design still makes absolutely no sense to me. Conversely it seems idiotic.

 

If there's say a 100 minute period, when the rad is extremely hot (I'm talking, from experiencing two different rads doing the very same thing, at at least twice if not 3x the heat generated as they do when releasing it)... it is ridiculous having this wastefully, sleep-interruptingly, released at a time when it's not wanted or needed.

 

The reason for the time at which it does this bizarre max-heat-release, has been explained, & perfectly easy to understand: cheap rate leccy. But if this 100 min period is wasted, it's nonsensical. It would make -more- sense to  have this charge block period, in the daytime even with a higher leccy rate, because this 100min max-release-period could be useable (albeit at an uncomfortablly hot 100 mins but far better this than waking up sweating buckets angry at such a waste of your radiator's heat).

 

 

 

 

 

 

Edited December 4, 2022 by zoothorn

[ProDave]

You DON'T want a storage heater in a bedroom.  The heating patterns of a bedroom are different to a living room.  More typical is to just have an electric panel heater in a bedroom, usually with a built in timer and thermostat.

 

You will probably need some heat in the evening before you go to bed, that will be at the peak rate.  But then it can stay on overnight with it's thermostat controlling the heat output and most of that will be at the off peak rate.  If you like a cool bedroom for sleeping, leave it off and use it's timer to come on just before you get up to warm the room.

[zoothorn]

11 minutes ago, ProDave said:

You DON'T want a storage heater in a bedroom.  The heating patterns of a bedroom are different to a living room.  More typical is to just have an electric panel heater in a bedroom, usually with a built in timer and thermostat.

 

You will probably need some heat in the evening before you go to bed, that will be at the peak rate.  But then it can stay on overnight with it's thermostat controlling the heat output and most of that will be at the off peak rate.  If you like a cool bedroom for sleeping, leave it off and use it's timer to come on just before you get up to warm the room.

Hi ProDave, but both my parents two bedrooms had storage heaters in when they moved there. They must have radiators in bedrooms, especially at their ages. So, the two I told them after alot of research were faulty, are in their bedroom & livingroom.
 

They then got onto a professional company, who replaced the old ones for new ones. No mention either before or at his assessment, ever mentioned they shouldn't have these radiators in bedrooms.

[Gill]

9 minutes ago, zoothorn said:

Hi ProDave, but both my parents two bedrooms had storage heaters in when they moved there. They must have radiators in bedrooms, especially at their ages. So, the two I told them after alot of research were faulty, are in their bedroom & livingroom.
 

They then got onto a professional company, who replaced the old ones for new ones. No mention either before or at his assessment, ever mentioned they shouldn't have these radiators in bedrooms.

 

My place has them in the both bedrooms - legacy from previous owner.   It's not unusual but it's far from ideal.   For the room that doubles as an office it works OK but only because we don't need heat in there at night.  Our bedroom - we had it on once and never again - like an oven overnight when we do not need the heat.  We have gone down the route @ProDave mentioned with an electric panel / timer/ thermostat to warm briefly before bed and use economy 7 to get the overnight and morning temperature we want.    That works for us as we're up and out early each day, don't use the bedroom during the day and hate sleeping in a hot room. 

 

That might not be the same for your parents if they are up later in the morning and use the room during the day.   As to why no one suggested this - I've yet to see any storage heater supplier really lay out the drawbacks of the system or highlight the possible alternatives.   

 

I'd say it's worth looking at the panel approach,  especially if you parents don't use the bedroom during the day. Obviously it's incredibly irritating after the outlay on the new storage heater but our cheap panel will probably payback reasonably quickly as it allows us to never switch on the bedroom storage heater for the full 7 hours.   

[SteamyTea]

Quite simply, if the storage heaters are overheating first thing in the morning, and are not heating during the late afternoon and evening, they are undersize (either though wrong usage of controls or actual physical capacity).

 

Yet again, temperature is being mixed up with power and energy.  They are different things. Learn the difference, it is three things to learn, not difficult.

[saveasteading]

Handy tip: when you dispose of the slow to respond storage heaters, the bricks are very useful in the greenhouse as heatsinks: they absorb heat in the day and release it into the evening.

The bricks are incredibly heavy and  are more like tiles. I think there is a lot of iron in them.

[SteamyTea]

41 minutes ago, saveasteading said:

I think there is a lot of iron in them.

https://en.wikipedia.org/wiki/Feolite

 

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