7 day immerson controller

tommy-g_3

Please excuse my spelling of immerson.
We have a flat that runs on economy 7. The immerson heater controls are very basic, off / timed or boost where it heats a small part of the tank.

I'm not convinced that we need it to heat for the full 7 hours at night, never ran out of hot water in 4 months. And nor do we need it at the weekends as we tend to be away most weekends.

Where can I get a digital timer that will allow me a bit more control and allow me not to have the thing on over the weekend without having to remember to switch it on/off?

victor2

Something like this might do:
http://www.screwfix.com/p/lap-digital-weekly-immersion-timer-240v/96608#

However, I would guess you'd be needing a sparky to install it and if so, one could probably recommend a unit and/or buy it at trade price.

penrhyn

Take your pick.

http://www.amazon.co.uk/s?ie=UTF8&field-keywords=immersion%20controller&index=blended&link_code=qs&sourceid=Mozilla-search&!!!!!firefox-uk-21

jalexa

tommy-g wrote: »

Where can I get a digital timer that will allow me a bit more control and allow me not to have the thing on over the weekend without having to remember to switch it on/off?

Ideas here... http://www.horstmann.co.uk/water-heating.php

...but at a glance weekend override isn't featured. However (possibly?) better "boost element" handling than Victor's suggestion which does have 7 day timing. Your choice. There are probably others on the market.

tommy-g_3

Thanks for the suggestions but I'm looking for an improvement on the Horsmann Economy 7 Quartz. (the website won't let me post a link as I'm a newby)

It has a preset timer that I can adjust and nor does it let me have it programmed to switch off at the weekend.

I should clarify that the tank is seperated with a smaller area at the top so you can boost it without heating the full tank, ie if you are doing it in the day time.

jalexa

tommy-g wrote: »

Thanks for the suggestions but I'm looking for an improvement on the Horsmann Economy 7 Quartz.

Here are some more choices, though I've drawn a blank so far finding 7 day control combined with separate boost element control. Really depends on your budget how to solve that. Separate boost element control perhaps.

http://www.tlc-direct.co.uk/Main_Index/Water_Heating_Index/Timers_Wired/index.html

Richie-from-the-Boro

Careful with what you think you are doing, an E7 cylinder has a 6kWh [two 3kWh] draw, and you should not be able to have both simultaneously on.

- some of these can be straight swapped, no need for a new back box or wiring
- the Electrisaver is what you are looking for, but not cheap
- red the datasheets & install guides

jalexa

Richie-from-the-Boro wrote: »

Careful with what you think you are doing, an E7 cylinder has a 6kWh [two 3kWh] draw, and you should not be able to have both simultaneously on.

That is a good point which may explain the "clunkiness" of some of the Horstmann stuff specifically designed for the E7 water heating market but I don't think it explains why the "top of the range" timer doesn't appear to have a 7 day (or weekend) setting.

Pincher

You can get a single channel programmer that can do 7 day (weekday/weekend) on/off switching. Use this to activate a 16amp AC relay which operates the bottom immersion element.

The programmer can have a one hour boost button, which will switch the bottom element on. The boost immersion element is simply not used.

I think you can get a two channel programmer that can directly switch 16amp, but I can't remember the brand.

tlh858

tommy-g wrote: »

I'm not convinced that we need it to heat for the full 7 hours at night

You won't be heating it for 7 hours - the thermostat will switch the element off as soon as the water is hot. It's probably only on for 2 or 3 hours at most. Less if there is some hot water left from the previous day.

Richie-from-the-Boro

I wonder if there's any need for this in the first place, the O/P has an old economy 7 quartz I assume with only two options / (1) OFF / (2) TIMED only + a clock + a boost.

- forget the [bottom element] boost
- set the clock wrong by +4 hours

The supplier teleswitches you over at say midnight and off at say 7am .. .. but your clock won't throw till 4am real. So the top element is switched to isolate and the bottom element is not live because your clock has not thrown the solenoid.

At 4am real the bottom element starts charging then at 7am real the supplier teleswitches you off, that circuit however is still open but no longer live and the boost is still isolated till 11am of the clock but because that circuit is not now live you will have received only 3 hours of cheap rate.

Your clock however is still running till 11am of the clock [3pm real] and will deny you a 'boost' facility even if you want it because it thinks it under the control of the teleswitch until 11am of the clock.

NOTE 01: One thing to consider, previously, the kettle was always half full of well insulated how water when the night rate switched on. Depending on their usage and the restricted three hours input they may well start the next night with a kettle full of stone cold water .. .. starting from cold may cost twice the price of starting from a hot half an cancel out any savings anyway.

NOTE 02 : It doesn't quite work that way with an on / off stat % on over time and 'electrical chaos theory' but you know what I mean.