Thermann Smart Electric Storage 315L

Had this smart system installed almost 2yrs now. App has worked flawlessly for us (Rural using Starlink 3). I initially set this to an hour in the morning to heat and an hour in the evening before we normally have showers. Rest of the day we dont need hot water do it dosnt need to work. Found out after 6months of use that it draws 3kw an hour in the antibacterial cycle once a week if settings are below 62 degrees celcius to prevent salmonella etc. Ok, fair enough we are on tank water so that is not a bad thing. Bad thing was it almost always tended to start thus cycle for up to 3hrs using 3kw an hour during peak time at night. We have a 15kw solar setup initially making on average 80kw a day, but with no way to run this antibacterial setting during the day when we are making 13+ kw an hour was not saving us cash. Instead it almost always started at the peak hour time.

Read about the non negotiable setting time bypass if we set the heater temp up to 65C, that it wont run the antibacterial cycle weekly. But it still does run the cycle monthly.

Fair enough, but it is still running this cycle anywhere from late afternoon to middle of the night. Now we have had a 50kwh battery installed this means the thermann is robbing us of around 9kw of battery 95 percent of the time when the sun has gone out with no way to control this.

This has irked me now to write this, as we are now trying to live off grid. With winter innthe bush a heater is necessary using quite abit of battery. One EV car & cooking etc at night runs the battery fairly low as it is, let alone a hotwater heater with a mind of its own robbing us of that extra 9kw of battery leaving us with bugger all to warm the house up in the frosty mornings.

So does this heater work? YES

Is this heater app adjustable? YES

Does this heater allow you to run that all important antibacterial cycle when the sun is in full bloom? NO.

Bad design from something as simple as an app option to do this.

I still cant figure out why it only runs this cycle mostly after the sun has gone out. If there is a powercut, the thermann will be the first thing to be switched off at the meter box as we dont need something stealing our power when we need it most without our permission.

Thermann fix this flaw please, and i’ll give you the 5 stars. Otherwise we wont be going with another one with such a bad energy wasting flaw you cannot control.

Was recommended to get a Thermann smart HWU by my plumber. Overall a great experience from Thermann and their support team. I had my smart HWU installed on a Monday, tried to connect it on the same day, but was experiencing some error messages in the app. I emailed Thermann on Monday evening, and by Tuesday support had contacted me to assist - I was able to speak to Chris direct who walked me through setup and wifi testing, and also provided tips regarding water temp and solar heating cycles to best make use of the solar. Friendly, easy to talk to, and knowledgeable support staff.

Very impressed with service / support, and as the HWU is new it will be a monitoring process for the next few weeks to get the best use out of the solar vs maintaining the desired water temp. The notion of the smart HWU being set and forget is great - it heats as scheduled without drawing unnecessary power.

Thermann Smart Hot Water, if only it was. OK it heats the hot water, but so does a $10 kettle. Their wireless controller, may not be compatible with your home WiFi router. Meaning be prepared to buy a new compatible router and or a Wifi booster/aerial at your expense. In my case another $500. Oh and you won't know if it works till you have the unit installed. In my case the app synced to my phone for about 5 minutes before the unit shut down. Had the WiFi tested again at my expense another $120 gone. Everything worked, router talked but then shut down. Scratch scratch let's buy a new router. Sigh.

And another feature of this "Smart" power saving, heat me please when you have solar to save money, is the unit does an antibacterial cycle, which heats the water above 62 degrees for 30 minutes. In my case it did this at night, so there goes any power savings for a day or so.

The App works but is clunky.

So is it worth paying the premium for the smart controller? In my case no. But it may suit your needs, unfortunately you may find out the expensive way.