1 water heating element, 2 feeds?

[styleruk]

I get the feeling asking this will produce head shaking, I'll ask anyway...

I have a hot water tank with a single immersion heater. Currently that is fed by a box I fitted that re-directs excess solar from my solar panels direct to the element (via the distribution board of course). That's all fine for summer and bright days.
Last winter I used a timer on the element to make use of middle of the night cheap rate to heat the water tank, but now I can't as I have it hooked up to the solar box.
my question is, is there a way to feed 2 power sources into one element. Or even, is there an element that has this ability, ie; 2 elements in one fitting.

Ideal result would be, I can heat the hot water in the night on a timer and also gain some from solar still, without buying a new tank or a fancier solar diverter.

cheers.

 

[styleruk]

I get the feeling asking this will produce head shaking, I'll ask anyway...

I have a hot water tank with a single immersion heater. Currently that is fed by a box I fitted that re-directs excess solar from my solar panels direct to the element (via the distribution board of course). That's all fine for summer and bright days.
Last winter I used a timer on the element to make use of middle of the night cheap rate to heat the water tank, but now I can't as I have it hooked up to the solar box.
my question is, is there a way to feed 2 power sources into one element. Or even, is there an element that has this ability, ie; 2 elements in one fitting.

Ideal result would be, I can heat the hot water in the night on a timer and also gain some from solar still, without buying a new tank or a fancier solar diverter.

cheers.

Already I feel stupid. Just googled it and found dual element heaters. I'll look at that, it seems the safest bet. Are there other options?

 

[Avo Mk8]

Google 'solar power diverter', or Solar iBoost etc.
sorry, just re-read and see you don't want to go that way!
Perhaps your dual element immersion is the way to go, as long as there is appropriate isolation between the elements. If there's only one over-temp. cutout, that might be a problem?

 

[styleruk]

Google 'solar power diverter', or Solar iBoost etc.
sorry, just re-read and see you don't want to go that way!

Yeah, already fitted one of them to heat water during the day. I was hoping there may be some kind of diode box that you can buy that you put 2 feeds into and only 1 comes out without putting power up the wrong way.

 

[Avo Mk8]

Yeah, already fitted one of them to heat water during the day. I was hoping there may be some kind of diode box that you can buy that you put 2 feeds into and only 1 comes out without putting power up the wrong way.

No , not with AC!
Relays or contactors with appropriate break before make, and safety interlocks to avoid BANG!
Not recommended for a DIY scheme!

Presumably you want automated, not the manual version:

Changeover Switch with Centre Off - 2 Pole

20A Changeover Switch with Centre Off, Kraus & Naimer

voltaconsolar.com

 

[styleruk]

No , not with AC!
Relays or contactors with appropriate break before make, and safety interlocks to avoid BANG!
Not recommended for a DIY scheme!

Tis the way I'm thinking. Looks like the dual element is the best route for me.

 

[brianmoooore]

What type of hot water cylinder do you have? If it's the type where you can access the actual copper of the tank, it's possible to add a boss for a second immersion heater.

 

[styleruk]

What type of hot water cylinder do you have? If it's the type where you can access the actual copper of the tank, it's possible to add a boss for a second immersion heater.

That is a possibility, but seems a bit excessive. If there is an easier way to do it, I will.