Recommendation Please - Economy 7 Immersion and Cylinder

[Marcelo]

Hi
Following on from my Economy 7 Immersion and Cylinder post I think i'm going to replace the 16 yr old system.

Can anyone recommend an unvented mains pressure cylinder with two immersions (at least 120 litres). If the E7 immersion is currently hard wired into the fuse box would the new one need to be or can i get one with a control?

 

[EFLImpudence]

Not a plumber so will leave any recommendations to others.

If the E7 immersion is currently hard wired into the fuse box would the new one need to be or can i get one with a control?

Not sure what you mean.
Hard-wired just means not on a plug and socket so yes you can fit a 20A switch and/or timer if you want, but it will still be hard-wired.

Theoretically a 3kW immersion should be alright on a plug and socket but some plugs and sockets don't cope well with a long-term immersion load.

 

[Marcelo]

Hard-wired just means not on a plug and socket so yes you can fit a 20A switch and/or timer if you want, but it will still be hard-wired.

Sorry, my wording wasn't very good

the element is connected to a distribution board (fusebox) that is only live during the 'off peak' tariff. So there is no control panel

 

[EFLImpudence]

What is it you want to do?

As I said, you can fit a 20A switch if you want to turn it off.

You can also fit a timer but there isn't really much point - if you want hot water.
The E7 supply will switch on at the prescribed time, heat the water until it is at the integral thermostat temperature (60° after two or three hours) and then the thermostat will switch it off and use no more electricity even though the E7 supply is still on.

 

[Marcelo]

What is it you want to do?

As I said, you can fit a 20A switch if you want to turn it off.

You can also fit a timer but there isn't really much point - if you want hot water.
The E7 supply will switch on at the prescribed time, heat the water until it is at the integral thermostat temperature (60° after two or three hours) and then the thermostat will switch it off and use no more electricity even though the E7 supply is still on.

Thanks. I've a better idea of how it works now.

I'll see if anyone can recommend a specific immersion and cylinder and stick with my current wiring setup

 

[JohnD]

... cylinder with two immersions (at least 120 litres). If the E7 immersion is currently hard wired into the fuse box would the new one need to be or can i get one with a control?

It is usual to have the lower element timer-controlled, and the top element manually switched, on the normal (untimed) supply, for use when you have used up all the cheap-rate hot water.

IIRC Hortsmann make an immersion heater control with this facility, I have an idea it is about *** edit: £80

Take some photos of your electriucity meter, consumer units and any other devices and controls around them. Quite likely you are on a modern tariff where all overnight electricity is at your reduced tariff, meaning that, if you have an immersion timer, you no longer need to use the timer that controls the off-peak consumer unit you mention. The timed unit is useful for storage heaters, as it saves you needing multiple timers.

If you are going for a new unvented cylinder with two immersion elements, I'd suggest a bigger one. most people like at least 200 litres. A bath uses about 100 litres.

 

[muggles]

Have you had your incoming mains flow rate and pressure checked to ensure it's actually suitable for an unvented cylinder?

 

[JohnD]

edit

this is the Horstmann I was thinking of. It is actually over £80.

https://www.tlc-direct.co.uk/Products/HOE7Q.html

They now also do a digital one at about the same price.

 

[Marcelo]

Have you had your incoming mains flow rate and pressure checked to ensure it's actually suitable for an unvented cylinder?

It has to be that I believe as i live in apartment and the cylinder is in a cupboard