Which TRV has lowest battery drain?

I have several Popp Radiator Thermostats with unresolved battery drain issues. These look to be very similar to Danfoss. Is there anybody with experience of these as well as other manufacturers?

I think

  • Popp is now Aeotec
  • Popp and Devolo are re-badged Danfoss

…so presumably no difference in battery consumption between these?
…or is it how the driver/app is written? I have all set to 1800 sec reporting interval (maximum for Popp). Is the interval the same for Danfoss/Devolo?

I think like the above, these don’t need another bridge?

  • Fibaro
  • Honeywell evohome

…but these do(?):

  • Tado
  • Netamo
  • TCP Smart Zigbee Hub

Anybody have such experience with any of these?

I think it’s not possible to make a general statement. As far as I know, each manufacturer has its own firmware. So it could possibly also be due to that as you guess.
But I guess the real factor is the wake-up interval. With a wake-up interval of 600 s, the battery lasts about half a year for me with a POPP radiator thermostat.
As far as I know a bad connection can also cause more drain on the battery.

According the manual of the Devolo TRV the wake-up interval can be set between 300 - 1800 s, but 300 s is recommended. And they say that the battery can last up to 2 years.

Right, you don’t need another bridge, it’s a Z-Wave device. But the Fibaro Heat Controller doesn’t work reliable with the actual Fibaro app. For more infos please search a little bit in the forum.

Batteries in my tado TRVs last about 18 months to 2 years.

Thanks for your replies (and the warning about Fibaro, which having read about I will skip)

It seems Aeotec also has a FLiRS specified TRV that is not originally Popp. I assume this might suffer the same Homey incomplete FLiRS implementation problem that might be the cause of the Fibraro issues? Does anyone have experience of this TRV? An Amazon review describes this as originally from original from manufacturer Eurotronic, and it seems plenty of issues with these and Homey too.

It seems Tuya has a Zigbee TRV, but it doesn’t seem to be listed in the devices in the Tuya Zigbee app

Batteries in my tado TRVs last about 18 months to 2 years.
@Adrian_Rockall That’s good to know. I’m not wild about about adding yet another bridge (or the expense) though…

Understand that, but it is a great standalone system that can be enhanced by Homey.
Just as well I have it at the moment as my Homey is dead.

I feel your pain: Mine, too - I had to buy a new one and start again (Homey’s backups were apparently lost too)
…Looking at the review thread somebody started, it seems Tado v3 now requires a subscription for smart features, and that the bridge and homey must be internet connected to transfer data…more complications…

The Aeotec and the POPP thermostat are completely different.
All FLiRS thermostats, also the one from Aeotec, have problems with Homey.

How long do the batteries last anyway?

Aeotec’s thermostat is the exact same thermostat as the Eurotronic one, just different IDs.

@fantross , Looks like Aeotec took over the Popp one, as well as the Eurotronic one.

How long do the batteries last anyway?

It varies, never more than 2-3 months, sometimes a matter of weeks

Power consumption for can vary greatly from one to the next. A lot has to do with how often the actuator opens and closes the valve and how much effort it takes to do so. For instance in another post someone describes how a Devolo moves the valve pretty much constantly.

Something to consider for instance is if the thermostat has open window detection and if a cold draft passes by it often. If that is set too sensitive the valve may behave as the Devolo owner describes.

In that case it may be wise to use Homey to build actual open windows detection instead of reacting to sudden cold, and turn the open windows detection of the TRV off.

Aeotecs TRV is based on the Eurotronic one, as @Caseda already mentioned. These are FLiRS TRVs.
The TRVs from Devolo and PoPP are based on the Danfoss TRV. So these are all the same TRVs with different firmwares/IDs. These are “normal” TRVs.

Afaik Aeotec and PoPP started a cooperation.

Thanks Edwin, yes I have been trying to find out how best to control them, and am using Markus Klinger’s Heating Scheduler app, with flows to call for heat via Fibaro relays and “disable” the schedule (which I think means turn off the heating, rather than simply abandon the schedule, but am waiting for clarification) if the windows are opened…

(I understand the VThermo app is supposed to do this without flows, but it is not working for me)

I can’t see any discernible pattern for why some drain faster than others, and why they all drain much faster than the predicted. The battery reporting is poor and inconsistent, and generally the indication of battery failure comes from one of the occupants moaning that the radiators are “boiling” when the batteries fail and the valves are fully opened.

As I understand it VThermo does indeed do actual window detection and uses a hysteresis to control how often the valve moves. Increasing that may save energy (at the cost of bigger temperature fluctuations.

I’m not sure what is more efficient: having the TRV pick the right amount of valve opening based on the temperature difference or having VThermo switch between full open full close.

Is is not uncommon to valve the batteries fail in the open position: opening is simply releasing the pressure on the pin while closing means pushing the pin inward, which takes a lot of effort.

I think that is correct. Luckily I have had mine for many years so all still free.

True, an Internet connection is required for full control but the schedules still work if the connection is lost.

I bought a Tado Homekit edition where Apple seems to have negotiated subscription free operation. I do not have anything else from Apple than an iPad, but that does not seem to matter.

Fun fact: screenshot from Android phone sais Auto assis lt is provided by Apple :grinning:

1 Like

Sadly I don’t have any apple stuff. But perhaps I should just bite the bullet and replace the whole set-up with Tado, if it just works and some redundancy in the event of another dead homey.

The trouble is I’d have to replace not just the TRVs but also 7 HeatIt Thermostats…Does anybody know if the HeatIt thermostats with floor sensors can be replaced directly with Tado equivalent?

The HeatIt’s look like this:

…but I can’t seem to find a Tado manual that shows a connection for a floor sensor?

This might be the blocking issue for tado. The Smart Thermostat doesn’t have an external temperature sensor facility.
I have wet underfloor heating so the water temperature is controlled by a separate thermostat at the manifold. Therefore the tado Smart Thermostat just controls the boiler heating demand wirelessly based on the room temperature and controls the underfloor heating pump and zone valve via its relay.

Is this one not compatible with the valve then?
It looks like the base unit but it isn’t because it cannot operate a boiler directly. If you put it in a zone with a valve it takes over as a temperature sensor.

That’s identical to the base one. It’s just how you configure it in the app that makes the difference.
If it is configured as the base one then it is the master controller that all the others talk to when heating is required.
The problem for @K_S is it doesn’t have an external temperature sensor input that monitors the underfloor heating element temperature. It can only monitor the room temperature.

Thanks @Adrian_Rockall , @Edwin_D , If I understand correctly, I could have Tado wall thermostats for the wet underfloor heating on my ground floor and choose to forego the extra safety of the floor sensor (to protect the wood?).

For the first floor radiators, I could use Tado TRVs, but I’m not quite clear how they would communicate their demand for heat to the boiler. They seem to have a product called a " Wireless Receiver". Would I need one of those as well?