After a full house repipe and most radiators changed as part of an upgrade to heat pump, I now have wall channels cut, or floorboards up. I can now run fully hidden power and signal wires to every single Radiator valve and room temp meter, before the plaster and carpenter come to smooth the walls and fix the floor. (locality: UK)
Seems this position is rare. Almost everyone is adding one or two smart TRVs here and there. This is possible because no wires. A few people do no like the regular battery changes and run a 3 or5 V supply to the smart battery TRV (?SRV).
It seems there are no graduated actuators that are quiet and will take signal and power. Am I being stupid here? I am expecting to do a thing no one does because reasons?
I found a DIY solution buying actuator, making housing wiring circuit, I could do that, but I am not sure I want to go down pathway. No 3d printing access. And not for 17 radiators.
I have googled, binged, ChatGPT’d, and Claude3’d this. I have searched HA docs and plugins. I have read:
giant list of links I cannot post - only 2 for new signups.
The smart TRVs seem to work on the radiator exit. There will be water temp too low to be useful on the exit, and roughly reflecting the room temp. Radiators are really convector air chimneys more than they are radiators, and so heat exchange to an induced room airflow. Cold air comes in at the base, where the exiting water is leaving, so the exiting water should reflect the under-heated fraction of room air temp (roughly-ish-kind-of-surrogate-marker). Is the thinking that this is close enough not to matter, and having a separate room temp probe elsewhere actually of limited additional benefit?
There are actuators that do on or off.
Then there is a a handful or less that does PWM to gradually control the actuator.
I got the on/off version and tried to control it with a PWM since it should in theory work, but the gradient was too steep and you got on/off behaviour anyway.
@Hellis81 I can’t see how any of the ones in your thread are actually remotely controllable? I’m fine with wifi, zigbee, z-wave or 433 mhz, and I think just on/off ones would do, but I can’t find any. What am I missing?
Salus Actuator 230v Water Underfloor Heating Manifold M30 T30NC 2 watts Thermal Valve Normally Closed Compatible with Salus Controls and Underfloor Heating Systems, Ideal for Energy Efficient Heating. Amazon.co.uk
I’m using Hubitat not HA for my setup but the principal is the same.
The hard part is setting up the demand based logic so that the boiler only turns on when a room demands it. Also having logic in place to determine if the combi boiler is heating when it shouldn’t be and all the valves are shut (damages some boilers long term apparently if no “loop” is fitted)
I just bought one on Amazon.
I picked a 230 volt, NC version.
This means you can’t get any heat when you are out of power unless you unscrew the actuator.
Just place the actuators switches in a group, the group state is on of any of them are on
