Economy 9 with immersion water tank

curious_badger

AndyPK wrote: »

Don't adjust the temperatures. They are fine.

You need to be sure you have an E9 meter.

I'm 99.9% certain it is an economy 9 meter, the meter itself is labelled as economy 9
Also, the digital display on the meter shows 2 rates (I looked at the meter at 3am this morning and it was just stating rate 2 - so all seems in order there).
EDF also told me the property is currently on the economy 9 tariff when I spoke to them on Friday.

Consumerist wrote: »

What you should also check is that the consumption is being registered on the correct tariff. Just because the element is being switched on doesn't necessarily mean the consumption is being charged at the cheap rate.

Should EDF be able to confirm this to me? I'm not sure how else I can check? Thanks

Consumerist

curious_badger wrote: »

. . . Should EDF be able to confirm this to me? I'm not sure how else I can check? Thanks

Probably not. The internal clocks often run fast or slow so although you should get your 2-hr slot of cheap rate, it could start or stop early or late.

It's my guess that the heating element will only turn on when both (1) the cheap-rate starts and (2) the thermostat demands heat. So the cheap rate may have started at 1:00 pm but there was no heat demand until 1:30 pm.

Edit
The only way to check the timing is if the tank is cold at 1:00pm and watch the meters to see when there is cheap-rate consumption after then.

curious_badger

Consumerist wrote: »

Probably not. The internal clocks often run fast or slow so although you should get your 2-hr slot of cheap rate, it could start or stop early or late.

It's my guess that the heating element will only turn on when both (1) the cheap-rate starts and (2) the thermostat demands heat. So the cheap rate may have started at 1:00 pm but there was no heat demand until 1:30 pm.

Edit
The only way to check the timing is if the tank is cold at 1:00pm and watch the meters to see when there is cheap-rate consumption after then.

That all makes sense, thanks for helping - I will be keeping an eye on the tank and meter from now on to ensure it all seems as expected

On the plus side, just ran a quick bath and the water was nicely heated ..by far the most hot water we've used in our 3 days here so far

stator

I may be wrong, but it doesn't look like you have any timer module attached at all, so the immersion heaters don't know whether your on cheap rate or not and would just turn on and off when the temperature of the water drops below the threshold.

Unless, is it possible to wire up a heater to the electric meter in a way that the power is only turned on when the cheap rate is activated? I don't think they do this, but it could be possible?

Richie-from-the-Boro

curious_badger wrote: »

Thanks for your reply, I have removed the silver caps of both elements and found a thermostat for each of the two respective elements ...

http://imgur.com/IDg5P51
This is the bottom element (currently switched on as per my first post). The thermostat is currently set at 63 (hard to see but there is an arrow within the black circle). Is this a suitable temperature? Or should I turn it down to about 50?

http://imgur.com/BPlLi4Y
This is the top element (currently switched off as per my first post). The thermostat is currently set at 60 (again, hard to see but the arrow is within the black circle). Is this a suitable temperature? Or should I turn it down a bit (athough, to be honest, I will probably not turn it on unless I find myself in need of expensive instant hot water!)

Thank you for helping, I am well out of my depth!

There's a reason they are set so high, legionella bacteria are dormant below 20°C and do not survive above 60°C.

curious_badger

Thank you everybody for all of your insights and help so far, I feel a lot better now in terms of how to efficiently use the immersion

stator wrote: »

I may be wrong, but it doesn't look like you have any timer module attached at all, so the immersion heaters don't know whether your on cheap rate or not and would just turn on and off when the temperature of the water drops below the threshold.

Unless, is it possible to wire up a heater to the electric meter in a way that the power is only turned on when the cheap rate is activated? I don't think they do this, but it could be possible?

That's right - no visual timer module anywhere, so I will definitely take your advice and will be turning it off in the morning and on before bed for my own peace of mind.

I will be interested to see how the hot supply fairs through the following day/evening, and I can utilise the 2 hours available during the afternoon if I can figure out when the 2 hour window begins.

I'm also going to get further insulation (or a suitable jacket) for the cylinder, the EPC (provided by the previous occupier) advises this will provide a £20 per year saving and will naturally lock the heat in for longer).

Richie-from-the-Boro wrote: »

There's a reason they are set so high, legionella bacteria are dormant below 20°C and do not survive above 60°C.

Good to know, I will leave them both at 60c - thanks!

System

All i do is leave it on i have never turned the water off i find e7 hot water to be cheaper than when i had combi. It should only come on during the off peak rates.

curious_badger

mackemps3 wrote: »

All i do is leave it on i have never turned the water off i find e7 hot water to be cheaper than when i had combi. It should only come on during the off peak rates.

I'm hoping it does only come on during E9 hours, if it did then I'd be inclined to leave it on continually.

Do you find you need to use the top-up to heat it on demand at all? Thanks

System

I have never needed use the immersion heater, stops hot all day

curious_badger

mackemps3 wrote: »

I have never needed use the immersion heater, stops hot all day

That's good then!
I turned the switch off earlier today and I'm about to turn It back on ..hopefully it won't begin heating up as it should only function during the eco9 hours - I will report my findings shortly ... (I'm talking about the regular switch which some advise to leave on permanently - not the boost!)