except that an electric shower delivers about a third as much hot water per minute. no such thing as a "decent" one, especially in winter.
and that heating water with electricity costs about five times as much as heating it with gas.
How to change immersion heater wiring
- Thread starter losferwords
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except that an electric shower delivers about a third as much hot water per minute. no such thing as a "decent" one, especially in winter.
and that heating water with electricity costs about five times as much as heating it with gas.
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The immersion heater has a thermostat so it stops using electricity as soon as it reaches target temperature*
A hot water cylinder is not like a radiator. it is heavily insulated to prevent heat escaping.
What colour is yours? if it is below modern standards you can add more. it is also very worthwhile lagging the hot water pipes, especially the one that comes out of the top of the cylinder.
*if yours doesn't, it is very dangerous and the fault needs to be rectified immediately.
I live in the middle of nowhere in Somerset, so unfortunately no mains gas.
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when I lived in a cottage surrounded by sugar-beet fields, I had no gas
the HW cylinder was heated with an immersion element, but also a gravity loop from the small multifuel stove, which also heated (slightly) a bathroom and a bedroom radiator.
I have a relation in Somerset with a much larger multifuel, which is fully pumped and heats the whole house, though she now regrets not getting a gas boiler.
I find our 9.5Kw perfectly adequate for the purpose of getting clean in winter or summer, that is the purpose of a shower. You suggest they deliver about 1/3 the amount of water and it costs five times as much - those figures don't quite hang together and would make a shower cost fifteen times as much for the same quantity of hot water, which is obviously wrong.
Gas per Kw was around 1/4 the the cost until recently, but cost are very much in the air at the moment and set to rise, plus the OP would not even seem to have gas, or he would be using it to heat the cylinder of water.
What the OP in fact has is a cylinder heated by electric and an electric shower will beat that easily in both convenience and cost grounds, saving both water cost and electric - assuming the OP is on a water meter.
My partner moved here from a combi heated shower, to using our decent spec. 9.5Kw electric shower, she has made no complaints about it at all, even preferring a shower to a bath.
blue is modern and well insulated.
If the immersion heater element's thermostat goes faulty, you will find that the water gets hotter and hotter if left permanently on, getting scalding hot and possibly eventually boiling. But as you have a blue cylinder the immersion heater will be quite modern and I expect it has an overheat cutout which will cut power if the thermostat fails and it overheats. If you take the plastic cap off (with the power turned off) you will probably see a manual reset button on the cutout.
This fault is rare, and usually seen on very old appliances, but the results can be very severe.
modern pipe lagging looks like this. It is a stiff but flexible polythene foam, very durable, and can be cut and trimmed with a breadknife, and vinyl tape will hold it tight on bends. Most likely the pipe coming out of the top of your cylinder is 22mm diameter. You can get a superior "bylaw" grade that is thicker, but you may not have room in your airing cupboard. This grade is not essential indoors in heated spaces.
i have no objection to a timer on an immersion, and it is important if you are on an "Economy 7" or similar tariff for cheap off-peak electricity; but if not, it is not important.
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I simply cannot believe you do not have a thermostat fitted in your cylinder, when it is run on E7, but to be certain...
Undo that nut on top, the metal top will then lift off - after isolating it. Under the cover you will see several element terminals plus an item with an slot to adjust it marked in degrees C or F - that is the thermostat. If in doubt, post a photo of it.
Very helpful thank you, guys. I will definitely check this as soon as possible.
I am glad that you are happy with it.
There's a photo with the original post
Now I've grasped your E7 setup.
I think a newer Horstmann timer might suit you. It can be wired in the way you describe, they offer both an digital and a "clock" type at the same price, and it's a good product.
It would be most economical to heat the entire cylinder overnight at the offpeak rate, but if you need an evening topup, it can do that.
Not a high bar then
But what about hot water on demand from the all the taps? Most people expect it nowadays, and he needs the cylinder plus immersion for that.
Not a high bar then
But what about hot water on demand from the all the taps? Most people expect it nowadays, and he needs the cylinder plus immersion for that.
He already has that, the water stored in the cylinder and heated overnight on E7 at cheap(er) rate. If he can ovoid using it all up showers, by using a more economical electric shower, he will have plenty of hot water. Despite JohnD's negativity, modern decent spec. electric shower are fine.
Right - I'm away for a quick (electric) shower, then a browse round the shops..
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