Eddi and Water Tank Immersion

DK1981 · 21-09-2023 3:55pm #1

Appreciate this topic may be discussed to death in other posts but would like to check my understanding please.

I think my immersion heater is the two element ( sink and bath) down from the top of tank with a single thermostat. ( dual safety thermostat)

when we have excess energy from the solar it heats tank 1 ( sink) and when temp on thermostat is reached it switches off ( doesn't go to tank 2).

im assuming this is because the thermostat is at top of the tank - so in essence would never heat tank 2 ( as thermostats would always have reached temperature if sink had been on)

just want to sense check that is correct?

I know i can make tank 2 (bath) a priority on the eddi if i want - but i just want to check that my understanding is correct when tank 1 is priority - given my immersion setup.

thanks

graememk · 21-09-2023 3:57pm

Simply, yes, the thermostat knocks both immersions off

The eddi should be set to heat the bath one

DK1981 · 21-09-2023 4:04pm

https://www.boards.ie/discussion/comment/121139251#Comment_121139251

Thanks.

Just curious what do people typically do - do they prioritise the sink element ( to get a reasonable amount of hot water) and then export to grid for the FIT with the excess, or do most people use the excess to heat a good bit of water ( bath element).

just curious - probably depdends on your requiremeent for water in the household maybe

graememk · 21-09-2023 4:15pm

Well now that measured export is in, eddis aren't really recommend anymore to try and save money.

They do have a place if you originally heated your water by an immersion or solid fuel(convenience for the solid fuel, don't have to light a fire in the summer!)

But with gas and oil being in the 10-15c/kWh region it's cheaper to heat your water via gas and oil and export the solar PV excess at 20+

So really it's up to you what you want to do, if heating the sink is giving you enough hot water, stick with that. Of not go bath or just heat it from another source

John mac · 21-09-2023 7:56pm

for mine i just connected the bath . so only have 1 element heating .

chewed · 26-09-2023 6:52pm

I'm still trying to figure out how my Eddi v Immersion works. I have it set to Tank 2 priority, but it never seems to do anything. It only heats tank 1 (sink) and then shuts off saying it's reached Max Temp. Even if I try to boost Tank 2, it will shut off after a few seconds.

Is this an issue with my immersion? Is there any way I can set it to heat Tank 2 when I want it to?

graememk · 26-09-2023 8:27pm

https://www.boards.ie/discussion/comment/121160755#Comment_121160755

you can change the priority what immersion is used first I think its in the eddi itself settings.

Couple of things to run through.

Do you have a dual immersion?

Assuming dual, is both wired up? if your hw tank is cold, can you boost tank 2.

How big is your HW tank.

When you boost tank1, what is the max power that the eddi goes to?

chewed · 26-09-2023 9:15pm

https://www.boards.ie/discussion/comment/121161181#Comment_121161181

Thanks for getting back...

Do you have a dual immersion?

I'm not sure. It used to have a Sink/Bath option so is this dual?

Assuming dual, is both wired up? if your hw tank is cold, can you boost tank 2.

No, Tank 2 is not boosting, it looks like it's about to start, but then switches off (on the app). Only Tank 1 will boost. When the solar installers put the Eddi in I asked them what Tank 2 was and they said to ignore it!

How big is your HW tank.

I've no idea

When you boost tank1, what is the max power that the eddi goes to?

On the app it goes to 2.7Kw when I boost Tank 1

con747 · 26-09-2023 9:33pm

https://www.boards.ie/discussion/comment/121161426#Comment_121161426

Looks like it's wired to the bath element. @graememk will confirm though I hope!

graememk · 26-09-2023 9:34pm

https://www.boards.ie/discussion/comment/121161426#Comment_121161426

As it is drawing 2.7kw it is likely the bath element it is connected to.

There is likely nothing is connected to tank 2. Which is fine, you would want to be using just the bath one. (Both share a thermostat so if you heated "sink" first it will also turn off the bath)

That thermostat could be turned up, but can put the hot water very hot so there can be a scald risk.

Now that we're in September.. nearly October I wouldn't change anything now, but are you still heating the water from gas/oil? Possibly the reason that the eddi it stopping, your water is already hot.

chewed · 27-09-2023 6:02am

Thanks. Yes i still use the gas to heat up the water but only at 5.30am for 1.5 hours

So, if it's heating Tank 2, how come the hot water only lasts a short while (e.g. if having a shower)?

AmpMan · 27-09-2023 7:02am

A picture paints a thousand words.

https://www.boards.ie/discussion/comment/121162121#Comment_121162121

You haven't said how big the tank is.

chewed · 27-09-2023 7:58am

https://www.boards.ie/discussion/comment/121162206#Comment_121162206

As I mentioned above, I've no idea how big the tank is.

Excuse my (plumbing) ignorance, but are you referring to the water tank in the attic?

AmpMan · 27-09-2023 8:45am

https://www.boards.ie/discussion/comment/121162368#Comment_121162368

No the hot water tank. Just measure the height & width and work it out.

chewed · 27-09-2023 8:58am

https://www.boards.ie/discussion/comment/121162549#Comment_121162549

The immersion tank (with the jacket on it)?

DC999 · 27-09-2023 10:15am

https://www.boards.ie/discussion/comment/121162622#Comment_121162622

Yeah. That's the one that pushes the hot water into taps. If it's decade's old it's likely 120liters /l ish. A pumped shower can use up to 20l a minute. That hot water from the tank is mixing with colder water too for the temp you set on the shower. So 1 hot shower can drain the tank.

A power shower is much lower around 6+l a minute.

chewed · 27-09-2023 11:54am

https://www.boards.ie/discussion/comment/121163025#Comment_121163025

OK cheers.

Just measured there and it's around 50cm wide and 90cm tall. It's probably around 22 years old now as the house was built in 2001

graememk · 27-09-2023 12:11pm

https://www.boards.ie/discussion/comment/121163550#Comment_121163550

roughly will be 150ish litres, the gas would have it well heated in the morning, and unless you were using a lot of water it wouldnt take much to maintain it.

for 150L

your gas boiler is likely 20 kw so it would have it hot in no time.

The devils · 22-01-2024 4:37pm

Anybody ever seen one these for sale ireland

https://www.google.com/search?q=safety+thermostat+hot+water&client=ms-android-samsung-ss&sca_esv=600207301&ei=iPCsZa-IBpzJhbIPs4m94Ao&oq=safety+thermostat+hot+water&gs_lp=EhNtb2JpbGUtZ3dzLXdpei1zZXJwIhtzYWZldHkgdGhlcm1vc3RhdCBob3Qgd2F0ZXIyBRAhGKABMgUQIRigATIFECEYnwVIwB1QAFjgF3AAeACQAQCYAcICoAHECaoBBzguMS4xLjG4AQPIAQD4AQHCAgUQABiABMICBhAAGBYYHsICCxAAGIAEGIoFGIYDwgIHECEYChigAeIDBBgAIEE&sclient=mobile-gws-wiz-serp#vhid=k-_ws-k380B4KM&vssid=l

graememk · 22-01-2024 6:24pm

https://www.boards.ie/discussion/comment/121655198#Comment_121655198

A hardware/plumbing merchant should have them, I think ive seen them before in the local topline store.

Eddi and Water Tank Immersion

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