Twin immersion same circuit?

[zaceverett]

I've purchased a horizontal unvented cylinder that has come with 2 immersion heaters.

I was hoping to use the same circuit the my existing tank used.

What's the best way to wire in for 2 immersions? Upgrade the 2.5mm radial?

Any suggestions welcome

 

[SJD]

If you only have one (presumably) 16A circuit, you can get a controller that connect two elements, but only allows one to be switched on at any one time. Typically used so the main lower element is put on at an off-peak time (over night) and the higher boost element when you need to top up the heat in the tank.

Edit: Or is this a large tank designed to use both elements together?

 

[mainline]

I've purchased a horizontal unvented cylinder that has come with 2 immersion heaters.

I was hoping to use the same circuit the my existing tank used.

What's the best way to wire in for 2 immersions? Upgrade the 2.5mm radial?

Any suggestions welcome

Do you have a two tariff supply ?

You could use a Bath / Sink mode switch using your existing wiring.

It may be beneficial to install two circuits if you have a peak and off-peak consumer unit.

 

[zaceverett]

Do you have a two tariff supply ?

You could use a Bath / Sink mode switch using your existing wiring.

It may be beneficial to install two circuits if you have a peak and off-peak consumer unit.

No just a single tariff. The tank is 250l horizontal which is why I guess they supply with two immersion.

 

[zaceverett]

No just a single tariff. The tank is 250l horizontal which is why I guess they supply with two immersion.

The tank is indirect so will be normally heated via boiler but we will use the immersion as a boost when we have lots more people waiting for showers etc

 

[bennie]

Do you need both immersion? If not just connect one.

 

[zaceverett]

Do you need both immersion? If not just connect one.

Good point, I'm guessing that if I wanted to use it without the boiler in case of breakdown then one immersion wouldn't be man enough.

 

[bennie]

One would do the job but if your planning on using both at the same time you'll have to either upgrade the cable and protective device or run a new circuit for the second immersion.

 

[mainline]

No just a single tariff. The tank is 250l horizontal which is why I guess they supply with two immersion.

They should never really be run together, the intention of having 2 elements is that the top element keeps the top part of the tank hot for use when you aren't needing lots of hot water.

The easiest way is to fit a bath/sink switch or as already said a controller.

 

[zaceverett]

They should never really be run together, the intention of having 2 elements is that the top element keeps the top part of the tank hot for use when you aren't needing lots of hot water.

The easiest way is to fit a bath/sink switch or as already said a controller.

I'm a bit confused here...There is no top or bottom?? It's a horizontal tank and they're both at the same level

 

[mainline]

I'm a bit confused here...There is no top or bottom?? It's a horizontal tank and they're both at the same level

Ahh different type to what i had in my head, so your one is not economy 7 type but a dual element which will heat the whole tank whichever element is used but will obviously do it quicker.

Unless you want faster heating of the tank, then just leave it on the one element, otherwise you will have to run a new circuit to run both at the same time.

 

[7029 dave]

Seen plenty of horizontal cylinders for electric wet CH systems but never indirect cylinders, just took a look they are quite big holds quite a few litres of water.

 

[zaceverett]

Seen plenty of horizontal cylinders for electric wet CH systems but never indirect cylinders, just took a look they are quite big holds quite a few litres of water.

It's full weight is 300kg, Ive had a structural engineer draw up the plans for a platform in the loft. Wouldn't want to put that kind of weight on my ceiling joists. Guess it would be ok if I had a support wall underneath but I haven't.

Thanks for the suggestions, looks like beefing up the cable is the best option at the moment.

 

[littlespark]

Where did you buy it from?

Won’t they have suggestions of how it should be connected up

 

[zaceverett]

Where did you buy it from?

Won’t they have suggestions of how it should be connected up

Got it from Screwfix. A g3 plumber will be connecting it up.
As it won't be a straight swap for the immersion looks like I'll be getting an electrician in. I wanted to check with the professionals on here what options were available.

Just wondering if I could have another consumer consumer unit linked off the main one just for boiler/pump immersion 1 and immersion 2??