Høiax Connected smart water heaters

I don’t feel like the device classes listed in Tutorial: Device Classes - Homey Apps SDK v3 covers the device this app try to control very well.

Does anyone have any strong feelings about what device class a “hot water tank” belongs under?
My best guesses would be one of:

  • heater (what I use currently)
  • kettle
  • thermostat

Any strong feelings about this? Should I change the device class?

Many thanks frodehg! I just installed Homey Pro and added Høiax connected without many problems (ithe login windows opened in chrome does not work though, only in the integrated browser of Homey-app).

I’m not an expert, but I appreciate your work to integrate Høiax, and let me know if I can test something.

I still don’t know well how to make the most use out of it, but as a first thing I’d like to setup the Høiax so that it does not work when electricity prices are highest. Is there a way to make this automatic, in combination with Tibber Pulse?

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Not sure if I can do anything about the login window outside of the app, it’s all from myUplink.com . All I do is to expose it with the oauth2 plugin.

There will be a new test version out very soon where I try to calculate the leakage heat to the surroundings of the tank. This should make it easier to visualize how much money is lost due to increased tank temperatures. I aim to use this as a guide towards how to regulate the tank in future versions. As an example it may be valuable to increase the heat level before a price increase so you have something to leech on if you turn of the power when the price is high, but if the heat leakage is too high this might reduce the savings and even cancel it out.

I do not have Tibber so I am not sure how their app work, but I am sure it exposes the electricity prices as any other app that exposes electricity prices. What you need to do is to create a flow that turns off the tank when the prices are higher than your acceptable limit and turn it on again when it is within your acceptable limit. (I will probably allow you to do this automatically in the app in the future for your convenience, but for now you have to use your own flows). I myself created one flow that calculates a moving average of the electricity prices over the last few days. Then, in the same flow I calculate an acceptable limit for the future price based on the moving average. Additionally if the price is rising the next 2 hours I accept higher prices now, while I reduce the limit of acceptance if the next 2 hours will have lower prices than the current. Of course you don’t have to do this the same way but this is how I do it currently at least. (using Power by the hour for future prices)

The new test version is out, please have a try if you want to test:

The only new feature is calculating the heat loss to the environment. This will not be reported before sufficient data has been collected (at minimum one hour)

If you want to test please have a try, and if it has problems you can always go back to the previous version by installing Hoiax App for Homey | Homey instead.

This test version will be kept in the testing stage for a while before it is being published as the correctness and reliability of the heat leakage calculation need to be verified.

Awesome! I have been looking to get this heater.
Now I will.

Is energy consumption reported to Homey?

Yes it is.

The app doesnt recognize the 300 L model correctly where the max effekt should be 3000 W

Indeed, this is a known limitation which i could not resolve before I knew the 300 liter model was on the market. And unfortunately they have not made the documentation for the 300 model available yet so I am not entirely clear how to identify it yet.

Can you please list the following items to me and I will attempt to add correct listing of the 300 liter model:

  • Nominal power of heating element 1: (as listed in the myUplink app under “General”/“Config”/“1.2 About”)
  • Nominal power of heating element 2: (as listed in the myUplink app under “General”/“Config”/“1.2 About”)
  • Tank volum (as listed in the myUplink app under “General”/“Config”/“1.3 Technical”, this is probably not 300, it was 187 for the 200 model)

If I am not mistaken you may have to delete the device from Homey once I have resolved this and attempt to reconnect it.

If I provide you with a test version that attempt to fix the connected 300 tank issues do you think you can test if it works properly before I make it public? (I only have the connected 200 tank so I am not able to do the testing myself)

Element 1: 1250 W
Element 2: 1750 W
Tank volume: 283 L

Thanks for looking into it :slight_smile:
Im not sure how to run beta/test apps on Homey though. I would need instructions but Id be happy to help if you let me know how

@Bernt_Espelien I have added Connected 300 support now, but I am unable to push it to testing because the Homey team is currently reviewing a big update I pushed a few days ago. Thus I will push the connected 300 fix to testing as soon as it is possible.

Meanwhile I wonder if you can help me with some data mining for the Connected 300 tank?
The current change under review is that the tank will report how much leakage heat it is to the environment. Since I only have measured it on a Connected 200 tank the leakage heat will not directly apply to the Connected 300 tank. If you can measure this for me it would be awsome.
All you have to do is to install the app called Archive Insights: Archive Insights App for Homey | Homey, then wait until you travel on vacation so the tank is idle for a few days. Then, for this period I would like you to set the tank heat to 85 degrees Celcius and hysteresis to 3 degrees. Then after minimum 3 days of the tank being idle (the more the merrier), dump the no.hoiax statistics from the Archive insights app and send me the file you got (make sure you select the smallest timing window that cover the duration of the holiday, e.g. preferably the 7 day window). This will allow me to calculate the leakage heat accurately.

EDIT: I would also need a dump of the temperature log for the ambient temperature around the tank, or if you don’t have it an average temperature reading.

Hi. Considering buying one of these tanks. Just a question for my own curiosity.
Wouldn’t the heat leakage depend on the surroundings of the tank? I would imagine that it would leak faster if, say the tank is placed in a cold basement, rather then for instance a heated bathroom?
How do you calculate this?

(sorry for english speaking users, I didn’t notice I answered in Norwegian before I was about to post this, too much to translate. I will try to be more vigilant next time, use google translate if necessary (not sure if they even sell this product outside Norway?))
Du kan finne mye informasjon om varmetap i beredere her:
Jeg har slått sammen alle konstanter i regnestykkene der og målt at Connected 200 kontinuerlig lekker 1.57 Watt per grad temperaturforskjell mellom rommet og tanken til omgivelsene. Dvs. at at om tanken er 50 grader varmere enn rommet lekker den 78.5 Watt.
For Connected 300 regner jeg med at den ligger omtrent 50% høyere, men uten å ha en måling kan jeg ikke si det sikkert.

I tillegg til dette passive varmetapet kommer et aktivt varmetap som kun forekommer når tanken er i bruk. Dette vil komme i form av varmelekasje ut kaldtvannsinntaket på tanken. Dette kommer fordi trykket i tanken endrer seg når vannet oppvarmes slik at trykket i beholderen er større enn vanntrykket utenfor tanken. Avhengig av hvordan tanken er montert vil dette enten lekke inn i kaldtvannssystemet i huset eller til et ekspansjonskar. Dette aktive varmetapet blir ikke målt men jeg har mistanke om at det utgjør en betydelig faktor om mulig større enn det passive varmetapet. Du kan selv sjekke dette ved å kjenne på kaldtvannsinntaket på tanken når du tapper kaldtvann i en kran (vent et minutt for å la varmen forplante seg gjennom røret). Jo større forskjell mellom trykk i tanken og trykk utenfor huset jo mer vil lekke ut så de største lekasjene kommer etter at du har varmet opp en iskald tank og prøver å tappe kaldtvann først når tanken er varm.

Konsekvensene av dette er at du får større (aktivt) varmetap når du prøver å smart-styre tanken enn når du prøver å holde konstant temperatur (doh… - men mulig det veies opp av mindre passivt varmetap). Hysteresis bør også settes så lavt som mulig for å holde trykket mest mulig konstant. Hvor mye dette har å si vet jeg ikke enda for jeg har ikke fått målt det nøyaktig enda, men skal prøve å finne det ut etter hvert så jeg har bedre forutsetninger for å lage et system for automatisk varmestyring etter strømpriser og effekt-tariffer.

@Bernt_Espelien you may now download the test version for Connected 300 here:

A reinstall of the device is not necessary. Everything should just fix itself (except if you have created flows with the incorrect max_power. These will no longer work and a new flow has to be created)

Thank you for your detailed answer :grin:

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Anyone else that want to test the update for Connected 300? I don’t want to publish the fix before someone with a Connected 300 tank has tested that it actually works.

Thank you for a great app! It works very good.

A request for some flow-cards, if this is possible.

I want to control my heater so that it only warms the water at night (when the prices are the lowest), and that it keeps the heat until the morning.

What I want is to say something like: “WHEN temperature is below X, AND date/time is between X and Y, THEN start heating”.

For now, the cards available is WHEN temperature drops…, but this doesn’t activate if the temperature already is below the stated temperature, only the moment it drops below this. This means that when it is night and the temperature is already below X, it will not continue the flow…

It would also be nice if the WHEN state could include a Time-card with “between”, and the AND state could have “temperature is below”.

This is possible already if you use the other trigger:
When date/time is X, AND Logic_card(Temperature is below Y) THEN start heating
And another one to end the heating cycle:
When date/time is Z, THEN stop heating

But I think this one would be more practical:
When time is 22:00 THEN increase target temperature
And another one to end the heating cycle:
When date/time is 6:00 THEN reduce target temperature

Btw. I am half way making a new app that will control all heating sources available to Homey according to your custom plan so that both prices and the new Norwegian power plan (effektprising) is accounted for. I will announce it in here when it is finished as it will simplify controlling the water heater greatly.

Looks good on the 300L now. Great work! Ill try and look into the heat leakage when im going on vacation!

Thanks @Bernt_Espelien, I’ll push out the new version to everyone then :slight_smile:

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As promised earlier the app to control all heating sources in your home to meet the new power tariff in Norway (as well as electricity prices) is now available. It can be installed from here: Sparegris App for Homey | Homey

Please note that the controlling unit of the Høiax connected water heater must be set “Homey” if you want the new app to function correctly.

If you spot any problems or have improvement suggestions please report them in the forum for the other app: Piggy Bank