Ok… I have a feeling in my bones that the TRV will not receive such functionality except for a simple trigger. 
Although I may be wrong, of course, who knows what the devs will come up with at ewelink.
It would probably be possible to do all the logic based on separate software because ewelink may never support it.
I’m being optimistic but really don’t feel that Sonoff have a full solution until these components are added. It would be good to get some guidance from a product manager in this forum.
Some of the functionality is there already where an external temperature sensor can trigger on/off the boiler so really it’s just a merging of functionality and adding a bit of extra logic.
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I managed to get boiler control working via Nest today. You need to use NodeRed just now until they do the iHost updates. I used this set of nodes
I’m new to this having purchased some TRVZBs due to my existing Tado system being able to deal with the size of my house (Long and thin with thick stone walls as opposed to being some form of Hollywood mansion!).
I bought three and a Bridge pro and was impressed by the range and overall valve control and so invested in 12 more, plus some mini switches to act as repeaters. However, although the end device tech seems really good, it overall there is much missing from what I can see before there is a heating control “solution”.
- Obviously straight off some form of boiler controller that would do the OR functionality for turning it on and the AND functionality for turning it off.
- The TRVs are not visible in the HA Ewelink Add-On, I’m currently awaiting the delivery of my USB dongle to try direct Zigbee control
- The TRVs are not visible in any of the Ewelink phone widgets
- I cannot get any Alexa visibility of the TRVs
- From the posts I see that some additional status support will be available in a Dec firmware release
- From what I can see from the posts iHost doesn’t do the job, with the TRVs not yet visible?
As someone with some experience in IT product offering development I would have expected there to be a series of interim solutions created by the Sonoff developers that described, with approved configurations, how to achieve a viable heating solution using the currently available capabilities. As the products develop, those templated solutions would then be refined to remove any workarounds required to circumvent currently missing functionality.
I’m certain that it would only take one of the Sonoff staff a couple of days to create an end to end solution design and document it ??
The TRV are visible on the iHost but only to big screen computers. The iHost interface is almost impossible to interact with on a phone or tablet. For most devices you can however cast from the iHost and this is well formatted, allowing local interaction with most devices. TRV are amazingly not supported. Means you can’t simply interact with them on a phone or tablet.
I’m currently investigating a work-around. You can read the temperature in Node Red and Create a virtual Zigbee Temperature sensor to which you can send temperature. Then from the normal scenes you can get your virtual atemperature Sensor to trigger switching to OFF/Manual(at X temp)/Auto. You can plot the temperature of the TRV using the Node Red dashboard (phone friendly). I think you could probably use virtual devices with values/toggles and then have them trigger automatic scenes thereby creating the impression it was manually controlled. Requires lots of automatic scenes though.
Incidentally I’m just investigating if it is possible to add the eWeLink Cube Palette to the Node Red on Home Assistant. I’m thinking it is for those with an iHost but haven’t got it working yet. If it is then it is quite easy to have devices appear in Home Assistant Node Red. Does seem to require an iHost (or probably NS Paenl Pro) to create virtual devices as they’re local Zigbee ones and don’t appear in the eWeLink Home Assistant integration.
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You’re absolutely right!
It is supported now, but the functionality is limited. Firstly, you cannot control the TRVZB device through the eWeLink app and consequently it is impossible to have it in NS Panel. You should think about some more useful way of integration. This what we have now is far from being sensible.
After all, expecting to be able to use an external sensor with the TRVZB is not an exotic or impossible request. I would suggest accepting this for implementation right now.
All good stuff! I’ve been reading with interest as I’m just about to switch to Sonoff valves on a combi-boiler system. I guess my approach is probably more inline with how they designed these valves to be used. I’m also very much wanting to stick with iHost for these critical type services, so will be sending my NS Panel’s back to Amazon! Happy to hear any comments though on my (very simple) design!
Having a combi, I am able to put a THR316D on the boiler heating demand circuit so that I can manually set times for the heating to be available or unavailable, or off completely in the winter months. I’m hoping I will be able to control the simple on/off function based on the times the heating is available using a timer scene. During on-times, the occupants of each room will be able to set the temperature higher or lower and leave the TRV at that level, or adjust as they see fit. The accuracy of the temperature is not vital to me as if they are cold they can turn the TRV up and if they are hot…yada yada yada!
The only issue this leaves is the instance where all TRV’s are satisfied, which would ideally then allow a “switch off” command to be sent to the THR316D to disable the demand circuit. TBH, it’s no biggie to me if this isn’t available yet, as I have restricted hours and two open loops (bathrooms) without TRV’s, that can stay nice and toasty during the winter months.
I’m awaiting my replacement iHost box to test the viability of all of this, and will report back. But if anyone has any comments in the meantime, please do feel free.
I guess we have to wait and see what options for automations there are in when they appear.
On an iHost you can already get a temperature using Node Red but I don’t think there is an open/closed status currently. There are these mystery channel 1 and channel 2. No idea what they are for but hopefully one of the channels will be open/closed status.
Not sure if this is what you mean but you can use the get-devices node to find out whether each radiator is in HEATING or KEEPING state.
payload[0].state.thermostat[“adaptive-recovery-status”].adaptiveRecoveryStatus
I just run a flow every 5 mins and switch on my Nest if any of the radiators need heat.
How do you activate the Nest? I have a Nest learning thermostat 3rd generation and created a google developer account to access it from home assistant but did not find a way to do it from Node Red on the iHost.
Hello, I read -most- of the posts here and in TRV Zigbee Thermostatic Radiator Valve - implementation of scene functions for correct control and would like to give my 2 cents.
First of all, I was “stopped” by this affirmation:
don’t get me wrong, I am NOT saying it is wrong or anything, I come from a country that doesn’t need heating systems in every house, lived 9 months in Southampton and not I am dealing with these things in the house where I live in Germany…
My house has a Junkers Boiler with its control (a little more modern than your Honeywell in the picture) and the “possibility” (not installed) of having a water tank for the warm-water supply, so “similar” to what you describe.
The only Radiator that has a “normal” valve is at the entrance, therefore I wonder if it has to do with what you mention (“emergency heat dump”).
But, the installation manual of the Junkers boiler and its control say that the control should be installed in a room in which the radiators DO NOT have thermostatic valves, but normal ones like the one in that radiator at the entrance.
There is a “good” reason for this, it has to do with the “control loop” for each thing. The Thermostatic Valve in itself is a control loop, the easiest one: “below a temperature, open valve, above a temperature, close valve”, with the hysteresis (“reaction delay”) provided b the system (the time for the extra hot water to heat the metal and to radiate in the air to the 5cms away were the thermostat actually is)
In this loop, there is one input (“set temperature”) and one output (open/close valve). We tend to think that we are controlling the temperature of the room, we are not, just on that point 5 cms away of the radiator. The moment we put the temperature further away, we change the hysteresis part of the loop.
What I found in my house: The Boiler control is in the living room (inside wall) and there is a very large radiator in the opposite wall under the window with a thermostatic valve with an extension-temperature probe which could be hung further. So right now it would be measuring the temperature before the Xmas Tree if I had not replaced it with the TRV. There is a second small radiator but its Valve is not working, so it is always off.
My “distant future” plan is similar to what others mention here, but since the Junkers control is analog (0-20V) it would be a little harder. Actually I measured the output of the controller and seams to have only this possibilities: about 5V: boiler off, above 15V: boiler full power, and two intermediate around 9 and 12V (not sure if it is the same) for middle power. Hacking this part will take me a while.
But supposing I already have the control signal, the decision for that control signal comes from a combination of temperature sensors. At this point, I wouldn’t need to control the valves of the thermostats, they should be controlled by their own individual loops, except maybe in the radiator in the same room of the Main Control of the Boiler (following the installation manual). The decision around these 3 or 4 possible settings for the boiler (including off) would come from a combination of all the thermometers in the house. Here I would NOT want to use the temperature of the thermostats, 5cms away from the radiator (that is my biggest conflict with these heater system! It is too close to be measuring the “stable state” of the room, but it works almost the same for “any room” where it could be installed). I would have a thermometer in the “most relevant” position of each room. I just put one under the junkers controller, since it doesn’t display the temperature and I suspect it is not calibrated, I have the settings in 30° for getting 20° So I would somehow make a “weighted average” of the temperatures in the different rooms (the weights would be a little empirical, including room size, if the room has windows, importance of the room being stable, etc), then decide how far away of my “expected value” is that, in order to choose the power to sent to the boiler. For those boilers with just an on/of dry contact its easier at this point.
so, as I just saw from updating eWelink to 5.2 (after reading the other thread) it includes as trigger if the TRV is heating or inactive, that is enough information from the TRV (as discussed in the other thread, if all the TRVs are inactive, the boiler can be turned off, if at least one is “heating”, the boiler should be turned on, and in my case for “several” TRVs heating, put full power!). I believe the “local” control should be left to the TRV control loop.
With this 5.2 update it should be possible to do what everyone wanted, to use the temperature of the thermostat for changing other things, including the temperature setting of the same thermostat??? It wouldn’t make sense but it is the only way to force open/close the valve, and I don’t expect to ever have a direct open/close valve control since that would be messing with the control loop of the thermostat itself…
Anyway, I just wrote what I have been “thinking out loud”, hope it gives you ideas.
You can’t do it directly as the nodered nest nodes don’t work with google auth. I use homebridge-nest with cookie authentication (no dev account needed). On nodered you can then use the homebridge nodes to control the nest. It’s been working for 4-6 weeks without issue. I have homebridge on a synology NAS but it could all be self contained on the iHost docker.
I have a virtual device on the ihost. If any TRVs needs heat they switch it on. The second flow checks the state and adjusts the target temp to -2/+2 of the current temp to switch the Nest on and off.
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I think that when you poll the temperatures of the sensors, you are actually getting the last one that your iHost (or NSPanel Pro in my case) received from the sensor itself. So that “Check if TRV Heating” periodic input will be giving the same values of the last read (when the sensors generated an event). It might be better to save them in local or global variables in node-red so you don’t need to poll, and you can know how old the value is. I would also include some checking of the online state of the sensors (I have a Temperature sensor far enough from the hub to be offline most of the time, and the temperature reported is the last one it sent)
Is it the “Turn off Upstairs Nest”? then it would be a virtual device for the Nest, that would explain everything I also created a Virtual device for my Alexa…
which one is your virtual device? Since I have a NSPanel, I am not sure if I can create new devices (The Register Device node seams to be for existing hardware and seams to work only in iHost)
I use register node in a one time flow to create the virtual device.
The purple nodes, ‘Turn Off Upstairs Nest’, 'Turn On Upstairs Nest switch it off and on. The ‘Check Call for Heat’ triggers on a change of state.
I can send you the node export if that helps
I have a node red dashboard with all the temperatures from the TRVs and various other temp sensors. 2-3 of the TRVs have disconnected over 4-6 weeks and you can see the temp drop to zero for that TRV. I’m going to modify it to generate some alerts.
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I have homebridge but have never spent much time exploring it. Which plug in do you use on homebridge?