Hello everyone,
I have issue with one of my sonoff trv’s. It is not responding and it is only displaying 2 things. First it lights up whole display and then it shows number 64. After that it goes dark for few second and it straits again.
I tried factory reset but it only start blinking FA for few seconds and then got back to same thing than before.
Did anyone encountered this issue before?
Thanks in advance
Replace the batteries with new ones.
That helped! Thanks 
but why it is doing this instead of showing F4 error? Also I bought 4 of those heads and used them with brand new batteries. Should I expect the same behavior with other ones? Ewe link app showed me that battery are almost full in every one of the heads
@ward
This is another eWeLink mystery. Looks like a bug introduced with the latest firmware version.
It is probably related to zinc-carbon batteries (or cheap ones) and their poor performance. TRVZB rejects them already at a voltage of 1.4 V, although it reports about 97%. I had the same problem (not only with TRVZB). Try alkaline batteries with higher power such as GP super, ultra etc. with a higher permitted current load.
Hello, I too have some problems with my TRVZB…I installed my first valve (no errors and paired with NSPanel Pro)
Just one thing…that valve never changes status to Heating!
I know of the hysteresis…but more than 4 degrees? (It was a test temperature)
EDIT: problem solved, i didn’t insert the piece of adapter that permits to the valve to close and open the radiator…just one thins: make it more understandable for newbies, because i understood that i made a mistake from a post on your github 
thank you anyway (what a noob am i? 
)
