Hey guys, I need a hand with something. I’ve got 11 of those Sonoff smart TRV valves, and I was wondering if I can make a scene for each one. Or is there a better way to do it? I want the heat to come on when the temperature drops below a certain point in each room
@benlion1972 , do you need to control a boiler when then TRV switches to HEATING mode? In Auto and Manual mode the TRV will open the valve when the temperature drops below the set temperature so you just need to ensure the boiler is running.
If you want any of the TRVZBs to fire up the Heating Boiler (Call For Heat) you will need to find out what electrical condition the boiler needs to make it fire (my boiler is a Bosch Worcester and it requires the closure of volt free contacts across 2 terminals to call for heat). For your TRVZBs you will need 2 scenes to control a device that makes your boiler call for heat- Scene 1 is when one or more of the TRVZBs are in ‘Heating’ Status and is written as if it is an OR gate. Scene 2 is when all of the TRVZBs are in ‘Keeping’ Status and is written as if it is an AND gate.
eg
SCENE 1 (Heating)
If any condition is met
IF
Smart Device TRVZB XXX Status Heating
Smart Device TRVZB XXX Status Heating
etc
THEN
Smart Device Sonoff Basic Switch for example ON
Effective Period Everyday 24 hours
SCENE 2 (Keeping)
If all conditions are met
IF
Smart Device TRVZB XXX Status Keeping
Smart Device TRVZB XXX Status Keeping
etc
THEN
Smart Device Sonoff Basic Switch for example OFF
Effective Period Everyday 24 hours
In the sample scenes I’ve shown a Sonoff Basic Switch as the target boiler switching device- it does not have voltage free relay contacts as an output but switches the full ac mains voltage to its output terminals. There are YouTube videos showing how to modify the Sonoff Basic switch to provide volt free normally open clean contacts. There are other Sonoff devices available that feature clean relay contacts.
Although I don’t use the scenes that I have exampled above I have experimented with them successfully with 5 TRVZBs in the IF statements. As you have 11 TRVZBs the IF statements may not allow that many devices to be specified.
In my own heating system for the switching devices I have the TRVZBs each control the channels of Sonoff 4CH Pro switches which provide clean volt free Normally Open/ Normally Closed change over contacts. As I have 9 TRVZBs and only 8 channels to switch the boiler then I use the same type of scenes in iHost for 2 of the TRVZBs. The Then command is sent 3 times with 5 seconds delay between each to improve reliability.
Good Luck with your project.
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