Why? Is it not working properly? Is it not big enough for the space it’s trying to heat? Does it run out of steam too soon?

Electric heating equipment is 100% efficient - every single watt it consumes is converted into heat. The differences lie in how and when that heat is delivered to the space it’s heating and to you.
  

It wouldn’t necessarily need to be rewired. If you’re currently on an Economy 7 plan, it’s likely that the storage heater is on a switched circuit that is only live during the plan’s offpeak hours. If you don’t want the savings that Economy 7 can bring, then that circuit could be set to be always live, or live at different hours to suit a different plan. Alternatively, a new heater could be connected to an unswitched circuit that is always live. Many storage heaters are wired to both circuits anyway.

That is very likely. If there is no timer for the immersion heater, it will rely on the meter to switch the power on and off so that it only runs during offpeak hours. It will depend on factors like how well insulated the tank is and what its thermostat is set to how long it takes to reach its target temperature and switch off. It’s usually unnecessary and indeed wasteful to have it powered up all the time, so it might be an idea to have a time switch fitted. It only takes two or three hours to heat up a tankful.   

You should look very carefully at what you’re likely to be paying for the electricity you use. We can’t help with that without knowing where you live, because the rates vary a lot around the country. I can say that in my own region, my offpeak rate on Economy 7 is 37% less than the peak rate. Offpeak is 29% cheaper than the single rate. The Economy 10 offpeak rate is 22% higher than it is for Economy 7, but its peak rate is 9% lower. 

You can see how much peak and offpeak electricity you used last winter by looking at your meter readings for, say, 1 October 2023 and 1 March 2024. You can then work out how much your heating and hot water would cost you today on Economy 7 and Economy 10 to see whether the extra perceived comfort is likely to be worth it. You may want to factor in how much you could save by using power-hungry appliances like the tumble dryer, the electric stove, the washing machine and even the hoover only during offpeak hours. It’s a lot of sums to do, if the is an important consideration. 

Thanks - The issue is i will be out majority of the day when the storage heater will let out most of the heat which is no good for me when i’m home at night at want it. It is the original installed heater that would have been put in with the property in approx 1980 something. What are the best options in this case? Another Storage heater or as above?

You’ll just have to do your sums, I’m afraid. If your heater isn’t performing as you’d like it to, then one possibility would be to upgrade it to a more modern one that retains the heat more effectively until you need it.

Again, I’ll say it depends a lot on where you live whether an OVO Economy 10 tariff would work better for you. In some places, the overnight slot is from midnight to 5 am, in others it’s from 4.30 to 7.30 am, with corresponding differences at the end of the day. Neither your current heater nor a new ‘more effective’ heater would fare very well in the first scenario, so you’d effectively be left with five or six offpeak hours during the day, the first slot while you’re still at work and the second some time after you get home. It might be all right at weekends … 

Modern storage heaters are often designed to take seven hours to charge up and dispense the heat at something like half the charging rate over the rest of the day. If you don’t need heat until later in the day, it won’t take so long to charge them up. 

Only you can decide what’s best for you, so spend as much time as it takes to do your research in order to come to the best solution. Please don’t just fall for the marketing hype from those trying to sell you high-tech heaters that don’t do anything other than convert variously expensive electricity into heat.

Can they be set to trickle out some heat during the day, then push out the remaining heat during the evening ? Also do an all-day regime say at weekends ?

There are no end of variations. My own not-very-modern Dimplex Quantum NSH have complicated timers to specify just when the fans should operate to blow warm air out, with a number (three?) of on/off settings for each day of the week. It’s quite normal to set them to push heat out for an hour or so in the early morning and not again until evening, so the house is (ostensibly) nice and warm when you get home from work. At weekends, you’d probably set them to ‘Comfort On’ (= fan blowing) all day, even though they might well run out of steam before tea. ‘Trickle’ might just mean the natural heat dispersion that’s bound to happen even though the fans aren’t operating.

Of course, it will depend a great deal on the specific circumstances how well or badly heaters like this will perform - size relative to the volume to be heated, quality of insulation, quantity of greenhouse-effect warming and so on, just like when you’re configuring your HP.

Thanks, that’s all very good to hear. As long as they come with a good instruction manual

Someone I know is considering buying a flat with old storage heaters and I’m telling them not to be put off by them.