TRV Zigbee Thermostatic Radiator Valve - implementation of scene functions for correct control

Hi everyone
I urge the creation of TRV tube scenes soon

for correct functioning of TRV valves, in almost all home systems, the situation we find ourselves is certainly the following:

For example we could have:

  • several radiators controllable with TRV valves
  • boiler to be switched on (example via a simple Sonoff Mini)

To achieve maximum results in terms of energy saving, the system should work like this:

-If the temperature set on the TRV valve falls below the set threshold, the valve opens and allows the flow of water to pass inside the radiator, heating it (and here the system is already designed to do this), assuming that the boiler is already in operation
But what if the boiler isn’t running? we cannot rely on an external sensor because it would not be synchronized with the valve temperature, therefore the system would not work optimally

in short, we need the scene that can understand that when any TRV valve opens (therefore the temperature set on it falls below the threshold) the system controls the switching on of an actuator (for example a Sonoff mini, R2 etc…) connected to the boiler…so that it turns on on demand when a room is cold

naturally when the temperature is reached, if all the valves are closed, the system must switch off the actuator that controls the boiler

at this point we would have a functional system (what other competitors already do)

I have already read in other posts that in fact this possibility of scenes does not exist… but perhaps if we highlight the post with other comments or suggestions to better implement the functions we will speed up the process

thank you all


TRV should send an ON command to MINI/R2 when the temperature drops below xyz?

Does TRV provide its Open/Close status in ewelink? Does it show the programmed temperature?

I think it could be done with scenes, although I may be wrong because I don’t have a TRV on hand.

Create a scene that will send an ON command to MINI when the TRV status changes to Open because its temperature has dropped below the set temperature, in this way, a moment after opening the TRV, it will start the boiler via MINI.

Set such scenes for each TRV. Even if the remaining TRVs send another ON command to the MINI, nothing bad will happen because it will already be ON.

In a similar way, we can control the OFF command procedure for MINI, i.e. when TRV has the Closed status, Off should be sent to MINI. The only problem here may be the fact that the first TRV will turn off the boiler and other rooms may still need heating, so here you would probably have to come up with something else.

If I understood correctly, although I’m not sure…

Yes, the operation is as you describe, but what I complain about is that it is not possible to select the change in state of the TRV valve or the temperature detected by the TRV as the scene trigger condition as they are not viewable.

as regards the problem of the first valve in OFF of a set of valves, it can be easily solved by creating a scene that triggers OFF of the sonoff MINI only if all the conditions are satisfied (all valves in the OFF state)

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I suspected that these variables would be missing… :frowning: Both in ewelink app and web?

One would almost want to say WTF who designed the logic for this system…

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And what variables are available for TRV in If and Then?

After all, it must have some control functionality, otherwise it… does the same as my analog thermostats, which cost much less money.

In IF zero option

This is the problem

In THEN you can modify the temperature or the mode of function (manual or auto or off) but non the ON

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So at the moment, ewelink and TRV are not working well.

Do you have a paid plan? The question is whether CAST supports TRV correctly?

Anyway, there are two ways to deal with this, at least that’s what I do with stubborn devices.

Extract device status from ewelink app or if available from CAST in web browser. And macro automation and MINI support via webhook… unfortunately you have to have a paid plan. Such a terrible prosthesis, but it will work. :slight_smile:

Option with ewelink web/cast.
You need a dedicated 24/7 device (desktop) that will have a web browser, for example Firefox, and install the PageProbe add-on. This add-on can observe live what is happening on the page that is loaded in the tab. It can also react to changes in keywords and selected page outlines/sections.
When the sequence is correct, it initiates a connection to webhook.
On the ewelink side, you create a scene for MINI, as a webhook trigger, and as an action, you know ON.

This will work if PageProbe is set correctly. I did it to read the Open/Close door sensor and different webhooks for both states.

The second option is almost the same, but instead of a browser and a PC, we need a phone/tab with Android and Macrodroid that will monitor changes in the ewelink app and send a webhook.

I know, it’s chaotic, but it can be done and it will be enough for some time, because who knows when and if they will add full TRV support in ewelink.

Unless you’re already doing it differently, this thread is just a reminder of the problem. :slight_smile:

Don’t tell me that the ewelink app/web doesn’t show the TRV Open/Close status either? :slight_smile:

I wouldn’t want to adopt a setup like that just yet. Yes, the app shows the status of the TRV valve, even if it is not very clear.

I hope for an update soon.

For now I’m thinking of adopting external temperature sensors in each room that activate the relevant valves and the boiler, even if it’s not possible to set the temperature quickly but only by changing the scene every time

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They are missing in iHost too. If you monitor the output channels using Node Red you could extract the temperature and then use it as a trigger, requires a device that has node Red (iHost and NS Panel alto I think). If you look at the debug logs I also get iHost security changes mixed in on the TRV channels though, which is super weird.

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The good news is as written by Daniel_Zhan Staff of SONOFF
“The TRVZB can be set as a trigger in eWeLink in the next upcoming update. DEC version.”

I’ve watched the TRV node Red outputs. Problem is there aren’t messages very often, so I’m a bit skeptical they will be that much use as triggers. Maybe a change of mode, valve opening or activation of window mode forces an update; haven’t tested though.
If you have an iHost it can do node Red you can already use 4 things as triggers

  1. temperature
  2. mode (man/auto/off)
  3. battery level
  4. rssi
    You can also display the temperature graphed on a phone using node Red, admittedly nor prettily. They’re missing from the iHost dashboard options so until then there is atleast an ugly way of getting around the limitation. No way to change any settings without a computer though.

I bought twelve Sonoff TRV’s and can’t use them until proper functionality is released. We urgently need functionality in an auto scene or alternative control that allows us to turn on the boiler (via Sonoff Mini) when any TRV temperature is low and turn off when any TRV temperature is high. If this isn’t available soon, I will have to send these back for a refund.

Less important but also valuable is adding the TRV to Cast display so the room temperature can be seen and a quick override on/off button is available.

It seems that Sonoff were too ambitious with the sale of the TRV when software functionality was not ready!

Perhaps they’re developing a specific boiler controller like the competition have and all these issues will be fixed but either way, this was bad planning and management by Sonoff.


You can try the method I wrote about above, PageProbe or MacroDroid…

This is not the most convenient solution to using TRV, but it will work.

I appreciate the suggestion but that’s only viable in a small percentage of deployments. Even with my 50+ devices, I no longer have a dedicated system that is always on and I don’t want one for this purpose. My goal with home automation is to reduce energy costs while automating regular actions to heighten security and make life easier. Think also about how a technophobe would deal with this. They’ve seen the jazzy marketing of Sonoff to inspire them to invest in Sonoff TRV but then find the basic tools to make their heating system work are missing from EWeLink. We need a solution that works ‘out of the box’ now.

Of course, I agree with you, TRV unfortunately looks like it was not implemented correctly in the ewelink environment on time.

And we, ordinary users, have no way to fix it ourselves. Yes, I can suggest some alternatives which, if someone absolutely needs to, already have a solution, but I wouldn’t want to do it like that with 50+ TRV units either.

Unfortunately, knowing the speed with which the company implements new versions of the software, this may not be a quick process and who knows whether it is even on the map. It’s quite clear that the devs are focusing heavily on iHost(CUBE) which is in a pretty bad state at the moment and as a result the TRV details may be much less important for them to do.

The truth is that many Sonoff products had or have major deficiencies/software problems, this is nothing new, it has been like this from the beginning.

And TRV is another product that sets an example of this: release it to the market as soon as possible and we will worry about the software later or not at all.

If Sonoff TRV were an ordinary, cheap, stand-alone device that does not have remote control and all it does is measure the temperature locally and control the valve as needed to maintain the temperature in the room. You could say ok…

But my analog thermostats can do the same for much less money. So the fact that TRV currently does not have the ability to be selected in the scene as a trigger (If) and select the variables we want to use, whether the valve is closed/open or the temperature has reached our C/F value, is a big problem and contradicts the automation and reasonableness of purchasing a TRV.

It’s the same as if the DW2 sensor was not able to be selected as a trigger, suddenly the point of using it is lost…

If you can’t wait for the iHost update, I’ve managed to get the TRVs to control my boiler via Nest using nodered. I’ve not used nodered before yesterday but used these nodes to interface with the iHost. GitHub - eWeLinkCUBE/node-red-contrib-ewelink-cube: Node-RED nodes to control eWeLink Cube.

The temperature events aren’t very frequent but I’m just polling the TRVs and checking for a ‘HEATING’ or ‘INACTIVE’ state every few minutes. If any of the TRV are in heating state, I’m using some Homebridge nodes to set my Nest thermostat.

The Nest flows are the more complex. If you just want to switch on a Sonoff switch to control the boiler than that’s a lot simpler. Took a bit of youtube and chatgpt to get there but not too difficult.

Am I wrong or does the new version 5.2 of ewelink allow you to have the status of the valves as a trigger?

you are not wrong :slight_smile:

I connected my TRV with ihost.
I would like to send the setpoint to the valve with Nodered, what can I do?