Economy 7 Immersion

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KMH

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Hi,

I am new to  this so please bear with me if I sound overtly ignorant....

After buying a very "original" 1960s "semi" I found that even with the horrible storage rads disconnected the electricity consumption was suspiciously high...

I was astounded to find that the water heater was on the normal "socket" circuit and so was maintaining 60 degrees C all day and at horrendous cost!

I thought that immersions were by default on the "ECO7" and the flex outlet in the airing cupboard suggests a bodge... 

I have now put a single gang socket into the situation and used a relatively cheap digital timer to turn the water on for one hour each early morning and might do the same with the storage rads or more modern replacements...

A question I would ask is; are these timers regarded as OK for this purpose? If not I would like to know of an inexpensive 1KW heater to lessen the water-heating load and which will serve to be usable from PV electricity...?

Any ideas?

 
Cheap,timers are usually cheap for a reason....they are nearly always shite

I also seem to recall a a Regulation saying 13 a socket outlets should not be used in a cylinder cupboard due to the high ambient temperature

I may well be wrong as I Know very little, and a LOT less than some of the people on here "think" they do

 
The normal arrangement is two immersion heaters on the tank.

The bottom one is wired to the off peak consumer unit and heats a full tank over night at the cheap rate.

The second one is half way up and can be switched manually at any time to top up the hot water if you have used all of it.

sometimes this is more conveniently done with something like a horstman boost controller.

Even if left on all the time it should not use that much. I suggest you need to have a look at your tank and consider upgrading it. As a very minimum it should be a foam lagged tank and all the pipework around it lagged, if not the heat losses will be horrendous.

Chances are a lot of stuff will need upgrading in this house so best start formulating a long term plan for a better heating and hot water system depending on what fuels you haev available.

 
You will probably find your bills going up now. Instead of maintaining a constant hot tank which will turn on and off via the thermostat you are heating the whole tank up. Letting it cool down. Heating it up and letting it cool down again.

 
Regarding the 'very original 1960s' bit,

it may well be in need of a rewire, the economy 7 may have been botched onto the standard supply and since disconnected, 

A PIR may well be in order, if not a complete rewire. 

 
You will probably find your bills going up now. Instead of maintaining a constant hot tank which will turn on and off via the thermostat you are heating the whole tank up. Letting it cool down. Heating it up and letting it cool down again.
erm... the hotter the tank to the surroundings, the more heat that will be lost...

 
Well done. 10/10. Why you quoted me I don't know.
If you switch it off when you are out and not using hot water, it will cool down and therefore heat losses will be less.

you implied that if you leave it on all the time so the tank is hot all the time that heat loss would be less.

 
If you switch it off when you are out and not using hot water, it will cool down and therefore heat losses will be less.

you implied that if you leave it on all the time so the tank is hot all the time that heat loss would be less.
No. I implied that if you switched on the tank only when you need it then it will use more energy heating a full tank up each time than if it is just maintaining a constant temperature.

 
No. I implied that if you switched on the tank only when you need it then it will use more energy heating a full tank up each time than if it is just maintaining a constant temperature.
That's madness.  How can it?

The energy it uses is the heat losses, and of course how much hot water you actually use.

If it's on all the time, the cylinder will be losing heat at a much higher rate.

If you  let it cool down, it will lose less heat.

But in the OP's case, I'll bet it's a poorly insulated tank and pipework that's the root of the problem, plus he's paying peak rate electricity not the off peak rate.

 
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Shouldn't water heaters be on their own circuit, and not fed from a ring/socket circuit?

What rating is the immersion heater (KW)?

Agree with ProDave about heat losses of cylinder. more insulation == ££s saved

 
Shouldn't water heaters be on their own circuit, and not fed from a ring/socket circuit?

What rating is the immersion heater (KW)?

Agree with ProDave about heat losses of cylinder. more insulation == ££s saved

Not under the 1960's regs - 1 socket circuit, 1 lighting circuit, 1 cooker circuit!

 
Well done. 10/10. Why you quoted me I don't know.
Well, to be fair, if we are being picky ( seems to be a recuring theme at present) he was not 'quoting', As he did not quote you.

Plagiarising ? Possibly

Refering to...? Possibly

Just saying

I have however been awake since 0330 so i may have missed something somewhere along the line

 
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Blimey does everything have to turn into a bun fight?

Original 1960's installation's are my speciality :lol: and if the OP is a cash buyer of an ex council property then they could be in for an even larger bill for bringing the electrical installation into 21st century.

Lack of main bonding is quite common, VIR is also quite common so steptoes suggestion of a periodic inspection is a valid one.

I'm off to greggs now to get some buns to throw at anyone leaving CEF maybe, just maybe I will get some sleep one day.

 
Thanks to you who responded - I was not aware that 1960s regs allowed the immersion to be on the main ring... My timer seems to be doing its job well (about a fiver from WILCO) ; I have been using it in low-power applications for years and it seems to be OK on the required 12 amps for 1.5 hours (6.30-8am each day). I am thinking of abandoning the storage rads for a 4kw gas fire for this winter to prevent hypothermia setting in (gas is in the cupboard but has never been used so have to pay £700 just to have the pipe verified!!!).

'Goin cold on PV now that the Govt. has threatened the FIT... 

I often go to the shops for buns late in the day to see if there are bargains - my standard breakfast is a pastry and a cup of good coffee - I refer to my bun-seeking trips as "Vultching"; there are many Vultures around at 5:30pm in Marks and Spencer where the fattiest buns are to be had....

 
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