My feature request is for TRVZB Valve Open and Close % to be available to set from iHost/ eWeLink scenes.
My reasoning for the request is that during the winter heating period we use the open % to balance the system radiators. During the summer non-heating period our heating system is switched into ‘SUMMER MODE’ which sets all TRVZBs to Manual with a target temperature of 35degC causing every TRVZB to be in the Open (Heating) condition at the set %. We are aware that every Monday at 12 noon local time the TRVZBs go through the CA process which includes opening and closing the valve mechanically. We would like to exercise the TRV valve pin more frequently that once a week to the full extent of its travel. We can achieve this but it means having to change the TRVZB open and close % to the default manually for Summer and then manually back to the Winter % settings. Apart from this scenario I believe that the performance of the TRVZB could be made more dynamic during the winter heating period without compromising battery life if the open and closed % could be available to use in scenes. Thank you.
@Staff-of-SONOFF please jump in an take a look
I did take a look and found that whatever the Valve Open % is set by the user at 12 noon (local time) on Mondays in the ‘CA’ process the valve opens fully to 100%.
Hello
I just have bought and installed my first TRVZB and find out % valve opening and closing…
Could You please explain what it is for?
I understand for example 60% opening and then full closing after reaching the set value… but what is closing % valve for? How the valve will work when I set open/close on 60% both ? Does it mean the valve will firstly open for 60% but never close because closing is set also on 60% ?
What are the differences between having them both on 60% or 60/30%?
Does it mean that setting 30% close valve will always left this valve open, and the warm/hot water will always flow through the installation?
I have read all instructions available but there is not a single word explanation…
For Valve Closing (%) 100%= Valve Fully Closed, 80%= Valve not fully closed but actually open 20%. You can use this feature for example if the TRVZB is fitted onto a bathroom radiator/ towel rail. If the bathroom is cold the valve will open to the set % when ‘Heating’ but when ‘Keeping’ the valve will only allow a low flow of heating water through the radiator if the boiler is ‘Firing’. This is useful as most boilers have Heating Over Run so that the circulating pump continues for a period of time after the boiler stops ‘Firing’. The slightly open TRVZB will provide a path for the circulating water when in over run condition and reduces strain on the circulating pump.
I still don`t get it…
If I set valve open at 50% and close 80% the figures doesn`t add up
In the first time when valve is totally closed and temperature drops below set value, the valve starts opening and goes up to set 50%… temperature raises above set value so the valve starts closing and goes down to 80% … how? If the procentage opening value was only 50% how the valve will close to 80% … will it reach -30% ? 
or maybe there are two separate scales , one for opening and the second for closing? but what for?
Maybe someone will explain to me how the valve will act if open set at 50% and close at 50% ? Does it mean the valve will not act at all?
It does add up but is confusing. Open % is the % measured from the valve fully closed position and the Close % is the % measured from the valve fully open (100%) position. If the open % and close % are both set at 50% the valve will stay open at 50% and not act. So yes you are correct there 2 scales with different datum points. You should also be aware that every Monday at 12 Noon (Local Time) the valve will carry out a Calibration/ De Calcification process where the valve will open and close by 100% regardless of the user open and close settings. In my own system I use the open % to balance the radiators to achieve the 11 deg C difference between the input and output pipes- this means that none of my TRVZBs are set to Open 100% on heating but all except one are set to Close 100% on keeping . The exception is one bathroom that has a valve close value of 72% on keeping so is actually open 28%. It means the radiator will be slightly warm if any other radiator is heating. It is good practice to have a bypass like this on the heating system to allow some flow on circulating pump over run or if the boiler starts up by its own frost protection.
If you fit the TRVZB head onto a new valve that is not fitted to a radiator you will be able to look into the valve port to watch the washer open and close with different % values.
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