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Z-Wave Eurotronic Comet Heating Thermostat

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Don't like waking up to a cold home or coming home to a warm home? Get the Comet Z-Wave Thermostat and adjust the heating to maintain exactly the right temperature from your smartphone. The smart heating thermostat also lets you schedule heating levels based on the time of the day, so that your home stays comfortable and cozy-- just the way you like it.

Apart from providing unmatched comfort, the smart thermostat also helps you save energy by automatically lowering your heating when it's not needed. The smart thermostat also comes with open window detection mechanism that automatically turns off the heating when the window is open, so that you don't unnecessarily increase the heating in your home. It's estimated that Comet Z-Wave Thermostat could help you save up to 30% of your heating costs.

You can either manually change the room temperature by adjusting the wheel or define intelligent scenes for automated heating control. The smart thermostat can be included into any existing Z-Wave network and controlled from your Z-Wave central controller. As a stand alone solution without a Z-Wave gateway device, you can program the thermostat up to 6 times for heating or cooling per day.

The intelligent thermostat comes with features like child protection, timer function, frost protection and many more functions that can be activated over the menu-driven display. It fits on most common valves, including Heimeier, Danfoss, Honeywell Braukmann, Honeywell, MNG, Oventrop and others.

Installing the Comet Heating Thermostat does not require any tools and can be performed without any technical knowledge – it's the simple! Just take off the conventional thermostat and install the Comet. No need to drain water. Adapters for most common valves (Danfoss RA, Danfoss RAV, Danfoss RAVL) are enclosed in the package. It comes with two years warranty, so you can buy with confidence.

Technical Details

  • Adjusting wheel for manual changes of the room temperature
  • Times for heating and cooling plus the temperature can be programmed
  • Quiet operation
  • Menu-driven control
  • “Open window” detection
  • Frost protection
  • Child protection
  • Timer function
  • Limestone protection
  • Vacation Mode
  • 6 switching points per day
  • Fits on most common valves (e.g. Heimeier, Danfoss, Honeywell Braukmann, Honeywell MNG, Oventrop since 1996 and others)
  • 3 adapters (Danfoss RA, Danfoss RAV, Danfoss RAVL) included in delivery – Further adapters can be ordered
  • Two years warranty
1.50 / 5.0
2 Reviews
5 Stars
4 Stars
3 Stars
2 Stars
1 Star
Very poor reliablity
You can't say they don't work, but in the end, having gained a lot of experience (8 months) with these and the ZPOPP valve, I have to say that these are a disaster. They are randomly unpredictable in every way conceivable. Batteries don't last long. They lose contact with the controller. The reset button inside is soon broken having had too many presses! The final nail in the coffin is that the manufacturer is almost rude to customers who approach them. My advice? AVOID! I'm throwing mine away and buying two more ZPOPPs that have been perfect.
27 Oct 2017
*Kind of* works, but barely adequate
After thoroughly testing this valve, I can't recommend it due to numerous reasons: - Its clearly a product for European continental market. Using it with UK CH systems will result in display being upside down in 90% of cases. It does not appear to be UK-specific version out there with opposite display (unlike, say, Honeywell valves). Ok, it maybe a minor niggle since display is auto-off most of the time anyway. - It does not follow Z-Wave protocol well. Particularly, its prone to abruptly going to sleep without processing all queued messages during wake up period. Obviously this will upset many controllers out there, and even if they will try to work around and mask the issue it will be perceived as very delayed response (as controller will have to send rest of messages in next wake up cycle). - Probably due to not following Z-Wave protocol well, it prone to stopping temperature & battery level reporting altogether, you have to poll it to make it reliable. - I consider temperature reports from radiator valves pretty much useless gimmick (after all they report temperature of hot air around the radiator which have only resemblance to actual room temperature if radiator was off for considerable time). However, this valve makes it even more useless because it only reports with 0.5 degree accuracy (and as I mentioned above, it prone to stopping reporting altogether). - Also, setpoint granularity is 0.5 degree too. It almost looks like valve does internal processing in 0.5 degree steps, but I hope not since it will make it pretty horrible as thermostat. - The motor is pretty noisy. Its certainly not a device for bedroom. - It eats batteries like nothing, I went from ~90 to ~65 percent in matter of week or two. Maybe because you have to set up wake up interval to be in order of ~5 minutes if you want any sane response delay due to aforementioned communication quirks (certainly it does not help). - only in direct control mode it works more or less ok - you can just set the actuator percentage from controller (and it will actuate during next wakeup). But then you need to have controller with some kind of aggregating algorithm and direct valve control - and if you already have such controller, any kind of wax thermo-electrical actuator connected to mains Z-wave dimmer will beat this valve (being completely silent, instant response and no need for batteries).
11 Apr 2016
Browse 8 questions Browse 8 questions and 11 answers
Why did you choose this?
Vesternet Store
I need to created a multizoned heating control for our village hall, controlled from the booking system, so this was my first choice to start experimenting/developing
JohnE 18 Nov 2016
I need to created a multizoned heating control for our village hall, controlled from the booking system, so this was my first choice to start experimenting/developing
JohnE 18 Nov 2016
To experiment with home Temperature control
Christopher M. 7 Apr 2016
To experiment with home Temperature control
Christopher M. 7 Apr 2016
Wanted to try out heating control for individual room / radiator.
Kevin M. 28 Aug 2016
Wanted to try out heating control for individual room / radiator.
Kevin M. 28 Aug 2016
To compare with danfoss trv
.Carl Erik .. 7 Feb 2016
To compare with danfoss trv
.Carl Erik .. 7 Feb 2016
Does this valve work with HS3/2 and the zstick v2?
Phill 12 Mar 2016
BEST ANSWER: We don't test products with HS, but there should be no reason this will not work. I believe the StellaZ worked in HS and this version uses a lot of the same internals.
Is this module reporting back to the controller when it enters MANU mode, and what temperature has been selected in Manual mode? I have a Vera Lite controller that needs to send my boiler instructions to switch ON if a higher temperature is selected, otherwise there is no point (for me) having a manual setting. The companies fact sheet also refers to being able to set 6 switch points per day. How do i configure that?
Hans v. 10 Mar 2016
Based on the manual and the pictures this expects the pipe to be either on the side or above the unit. In the UK most valves sit on top of the pipe. This gives the impression that this item and the LCD will be displayed upside down. Is that the case or is it possible to adjust or specify which way around?
Gary R. 8 Mar 2016
BEST ANSWER: As far as we're aware the orientation of the display can't be changed, so the way up the screen is will be determined by how your radiators are piped. Most people will use these by controlling them remotely though via Z-Wave using a smartphone or tablet App, so the display orientation isn't that crucial - after all, it wouldn't be Home Automation if you keep having to adjust / check them locally!
I have just purchased one of these. Two problems: (1) the manual refers to a button and I cannot see this and (2) my Vera Edge does not list this as a device?
peter c. 15 Feb 2016
BEST ANSWER: Please raise a Technical Support request using one of the following methods: 1) Clicking on the "Support" link at the top of any page of the Vesternet web site 2) Completing the form at 3) Emailing One of our Technical Support team members will be glad to assist you further!
Does this support the 'Direct' mode like the other StellaZ valve?
Guest Visitor 13 Jan 2016
BEST ANSWER: As we've said earlier on this device. It is based on the same internals as StallZ, so will have the same behaviour. However, using direct mode will very much depend on which Z-Wave controller you're using as most don't allow communication in that 'raw' manner. You usually use the device as a thermostat and just change its setpoint.
Does this unit report temperature back to the Z-Wave network?
Guest Visitor 11 Jan 2016
BEST ANSWER: The Comet is based on the same internals as the StellaZ, so it will have the same behaviour. It will report the temperature back to the Z-Wave controller.
Whats the main differences between the Comet and the StellaZ?
john h. 5 Jan 2016
BEST ANSWER: The main difference is the Comet has an LCD. Other than that they work in a very similar way.

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