Eurotronic Stella Z vs. Danfoss Thermostat

[macpiciu]

Hi all,

I just thought I'll share my experiences with Eurotronic Stella Z Thermostat vs. Danfoss Living Connect. I own both devices and manage them though Razberry board. First of all visuals, if your spouse, girlfriend, buddy or whoever you share the same living space has any sense of aesthetics and will butcher you for buying no matter how functional but ugly device stay away from Stella Z. It is the lowest grade of Chinese plastic, the look and feel is just awful, manufacturing quality is nonexistent. It looks like an accidental product that you wouldn't want to spend EUR 45 on. Quality wise Danfoss looks and feels like it's worth it's pricetag.

Functionality Stella-Z:
+ Temp sensor built in
+ Four predefined operation modes (eco, comfort, frost protection, manual)
+ Very quick radiator installation process
+ Seems to have very good battery saving

- Very poor quality include/wake button
- High chance of immediate internal error state after installation
- Mounting is unstable (dual latch)
- No direct manual override (although kid owner may take it as an advantage )
- Fragile mounting, the device is fixed in mounting position

Functionality Danfoss LC:
+ Direct manual override
+ Very stable mounting
+ Head turns in its axis (no damage if someone tries to 'manually' twist to adjust temp)
+ Factory reset capability

- Panic mode risk
- Battery drain risk

Based on the above I would still highly recommend going for Danfoss if you want quality and functionality in one package with the minus of risking the device going into Panic mode. Stella Z has its own potential with temp sensor and no manual override for locations where you want absolute control and no accidental temp changes.

My personal experience shows that Danfoss is excellent for locations like bathrooms where the manual access is very much welcomed. If I want to take a shower or bath in warm environment I shouldn't have to access smart home app. Stella Z works well in kids rooms where I don't want them to play with valves.

All-in-all I'm not happy with Stella Z as the look, feel and quality is way below Danfoss LC and their prices are the same.

[krambriw]

Which version do you have?

Living Connect (014G0002) or Living Connect Z (014G0012)

[macpiciu]

I have the Living Connect Z (014G0012) versions.

[pz1]

I did throw it away because Danfoss did not want to give support on it.

Edit: An earlier reponse about my DLC/StellaZ experience disappeared from this thread; so this response does no longer makes sense

[macpiciu]

I've read your previous comments, and for once they were never part of this thread, second you never made any solid claims. Moreover, you never mentioned StellaZ just complained that Danfoss told you that their device is as is, which in the case of any hardware you buy is the case, I've never seen dishwasher or kettle getting upgraded.

[pz1]

I have run a pre-production version of StellaZ since May. I never had the panic situation that I usually had with DLC. I had my doubts about StellaZ battery usage. Also I got far better response to changes in temperature settings. At 5 minute wake-up intervals, for DLC it took from 45 minutes to an hour and a half. StellaZ adapts immediately. I think the reason for that is that DLC is a PID controller, whereas StellaZ has direct control. Both approaches have their advantages. For my experiments the StellaZ with its quick response to central commands seems better suited.
PS: I've seen field upgradeable Z-Wave devices

[Jaume]

StellaZ have temperature sensor queriable from z-wave controller? haven't it Danfoss LC? With Danfoss if you wanna choose temperature dynamically from controller you must have an extra temperature sensor on the room? I don't understand very well how those radiator valvles works...

[pz1]

StellaZ have temperature sensor queriable from z-wave controller?
yes, and the reported temperatures of the five devices I have come pretty close to what my calibrated sensor shows.

[pz1]

Functionality Stella-Z:
---lines deleted
- Very poor quality include/wake button
---lines deleted

Within two weeks I lost two of these devices due to an apparantly failing include button.

As a matter of fact from the 26 Z-Wave devices I had in the past three years, 5 gave serious problems. The others were a Fibaro Wall plug, a ZWave.me wall switch, and a Everspring Smoke detector. Some of the 230V devices are so fragile that I am surprised they are allowed on the market.