The TRV is running out of calibration when trying to close to 0 from small steps like 1 or 2%.
So it will loose the calibration more often. I noticed this behaivor especially after using the adaptive mode.
The weekly calibration is pretty useless. The TRV will run out of calibration after 1 or 2 days. We need a feature to force calibration.
And we need a mode, where the TRV extra applies force to the motor when closing. (More current. Should be possible with a stepper motor).
I have made the same observation. For me, mostly after 1 week calibration gets lost and valves do not entirely close anymore. I had opened a discussion on the VTherm forum about it here: Phyiscal valve still open, while VTherm shows 0% open ¡ jmcollin78/versatile_thermostat ¡ Discussion #1749 ¡ GitHub - and some other users had the same problems. It doesnât look like a Vtherm issue though. It would be really great, if this issue could be addressed by some fix provided by Sonoff.
Have a look on this thread:
Im doing it like him. Just closing to like 10%, then when it has to close fully, it will go up to 100%, then go down to 0% in a full cycle. No small steps. This is working pretty great so far. No calibrationlosses.
If you read this thread carefully, you will see the valve wont open from 1%, i did a test on my radiators and i let them open percent by percent with 10minutes inbetween. And i measured the radiators incoming temperature. At 18% opening, the hot water came into the radiator. And once its startet, you can go down to like 10-14%.
I made a custom controlling script with a PI controller, and it only acts between 18% to start, then it only need to go up to 30% and down to 10% to maintain the temperature.
To close it, it just go up to 100%, then back to 0%.