Changeover switching for Economy 7 immersion element

[SamKB]

We've got a standard water tank with a bottom element fed from the economy7 wiring, and a top, "boost " element wired to the standard wiring.
Unfortunately it's quite a small tank and if someone has a bath in the morning
there is no hot water left, and the boost only heats the top of the tank so not enough for the rest of the family/day.
I was considering ways to "Boost" the main element, but obviously, just wiring to the same element would backfeed the economy 7 wiring, and could supply a nasty surprise for someone in the future, so it seems to me, the only sensible arrangement would be to use a suitably rated double pole 2 way switch to connect either the economy 7 wiring or the normal mains to the element, or rather to the fused switch feeding the element.
I know this will work, but is there any reason I shouldn't do it that I've missed ?

 

[flameport]

a suitably rated double pole 2 way switch

If you can find such an item, then that could be used, and it would very likely be left on 'boost' all the time.

Or use the device designed for the purpose:
https://www.tlc-direct.co.uk/Products/HOBX2000.html

 

[Taylortwocities]

Whssign

• Taylortwocities
• 16 Jul 2016

What he said

The Horstmann product in the link allows you to select a 1 or 2 hour boost, then it switches back to normal off peak operation. better than other solutions that allow you to leave the heater connected to more expensive peak time lekky, should you forget to switch the boost off

 

[SUNRAY]

If you can find such an item, then that could be used, and it would very likely be left on 'boost' all the time.

Or use the device designed for the purpose:
https://www.tlc-direct.co.uk/Products/HOBX2000.html

That's the kiddie to use and none of my tenants have failed to understand it.

 

[SamKB]

If you can find such an item, then that could be used, and it would very likely be left on 'boost' all the time.

Or use the device designed for the purpose:
https://www.tlc-direct.co.uk/Products/HOBX2000.html

Brilliant, just what I was looking for: I had thought such a thing should be available, but hadn't been able to find one, but had found the double pole two way 20A. Thanks.

 

[Taylortwocities]

You'd need a double pole change over switch. Something like THIS
Better to use the Horstmann.

 

[SamKB]

You'd need a double pole change over switch. Something like THIS
Better to use the Horstmann.

I was thinking more like this, but I agree the Horstmann is preferable

 

[Taylortwocities]

I was thinking more like this, but I agree the Horstmann is preferable

That will not work. That is an on/off switch that turns on and off the line and neutral connections. That is what double pole means.
to do what you want, you need a DOUBLE POLE , CHANGEOVER switch.

 

[winston1]

That will not work. That is an on/off switch that turns on and off the line and neutral connections. That is what double pole means.
to do what you want, you need a DOUBLE POLE , CHANGEOVER switch.

It clearly says double pole, 2 way. That is the same thing. It WILL work.

 

[Taylortwocities]

Hmm, I hate to say this but (this time) you may be right.

 

[SamKB]

This time Winston1 is right; that's why I linked to that particular switch. I wasn't asking if it would work, just if there was any reason to not use it.
Just a matter of terminology. Coming from an electronics side of things I was looking for DPDT (double pole double throw), and as mentioned in the title, was also thinking in terms of Changeover, but soon realised that "two way" was commonly used in household switch terminology, which turned up that possibility.

 

[SamKB]

Hmm, I hate to say this but (this time) you may be right.

This time Winston1 is right; that's why I linked to that particular switch. I wasn't asking if it would work, just if there was any reason to not use it.
Just a matter of terminology. Coming from an electronics side of things I was looking for DPDT (double pole double throw), and as mentioned in the title, was also thinking in terms of Changeover, but soon realised that "two way" was commonly used in household switch terminology, which turned up that possibility.

 

[winston1]

This time Winston1 is right; that's why I linked to that particular switch. I wasn't asking if it would work, just if there was any reason to not use it.
Just a matter of terminology. Coming from an electronics side of things I was looking for DPDT (double pole double throw), and as mentioned in the title, was also thinking in terms of Changeover, but soon realised that "two way" was commonly used in household switch terminology, which turned up that possibility.

Actually I'm normally right.

 

[DetlefSchmitz]

 

[crystal ball]