3rd gen learning thermostat - ring display stops working

[Nick_J1]

I have a free-standing 3rd gen learning thermostat (so it's not wired into the wall), it's powered by micro-usb connected into the back plate, serving 5V.  It's connected to my Heat Link and there are no problems with that.  My problem seems to be solely with the ring hardware.  The display won't work after a short time.

My thermostat is connected to the phone app, and when I check the technical info, it reports around 3.9V battery.

The software is up to date - I checked that whilst the ring was behaving properly, a couple of hours ago.

I have used the reset procedure.  It seems to work, but without the display coming on, I can't really tell.  But the app thinks it is OK.

So I have taken the front plate off, and directly powered the face with the micro usb cable.  After about 30 minutes (green light flashing), a message will come on the display saying to connect to the backplate to use the thermostat.  This, to me, indicates it has got enough power to run the display, and tell me this.  Is that a fair assumption?

So I reconnect it, making sure the connector is lined up, and it clicks into place... and it works.  For about an hour.  Then the display stops working.  This has been a daily thing for about a week now.

I suspect this is because the internal battery is draining, which would indicate the power isn't being supplied to it from the back plate.

Now, I *think* the ring still allows me to change temperature, because I see a response on the phone app.  But as I can't use the display on the ring, I can't use any other functions - I'm basically having to use the app to control my heating system.

Is this a common problem?  Do I need to take it apart to replace the internal batteries, or is there another solution?

Thanks for any advice.

[Frustratedddd]

The first thing, the battery showing 3.9v and that is very good. The display will work right down to 3.6v and maybe less. Internet connections and app linking then will not connect at that voltage.

You say a reset has been done, do you mean a factory reset?

When the display is working, have you checked the voltage say about 30 mins later?

The other thing, about a week or so ago the software was updated, that may have given you an issue perhaps?

Latest software is 5.9.5-2

[Nick_J1]

Hi, thanks for the reply. 

I've been checking the voltage via the app, and the lowest it has got to has been around 3.3V when it's plugged into the back plate and the display wasn't working.

The software is v5.9.5-2.  I have read somewhere that constantly flashing green light could mean the software download froze; that flashing green light is certainly a symptom I'm seeing right now.   But previously when I've reconnected the whole device, and it works for a while, everything seems fine, so doesn't really scream software crash to me (but I'm a software engineer, I'll always blame hardware first ;D) .

I have only done a number of soft reboots (10 second holding the ring).  I haven't tried a factory reset, that's something I'd always do as a last resort.  I want to exhaust all other options before going nuclear on it.

Do you think a factory reset would be a viable next step?