Originally posted by Dean
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If it comes back on again well after 5 minutes then yes you have a problem - I have seen this happen once or twice before, sometimes the spurious relay activation only lasts a few seconds despite my minimum on time of one minute...(minimum on time is not enforced if the heat demand is removed part way through the on period)
I really wish there was an event logging system in this device which I am sure would also assist engineers that come across problems that records the controller actions, such as BDR91 on/off, zone request change/confirmed, zone temperature etc or even if this information was just sent to Honeywell servers which could be accessed in the online portal/mobile app (which would be preference).
Another issue I notice as the controller is directly in my line of sight is that during the hour, the EvoHome Controller Internal Temperature sensor drops by 0.5c for exactly one minute 2-3 times an hour and then back to previous temperature (e.g. shows 19.5c then drops to 19c for one minute then back up to 19.5 again multiple times, also occurs at different temperature settings), with or without heating on, no draughts, various times of the day/night, controller in middle of the room and separate thermometer next to controller shows a stable temperature. At first I thought it was due to the controller trickle charging the batteries, but the same effect is seen out of the base unit.
I put it down to the fact that the built in sensor has a much more frequent "refresh" interval than all other remote sensors. I believe HR92's and DTS92's only send out a temperature update once every 4 minutes, so if the temperature is right on the threshold of changing from one 0.5 increment to another it could only do it at most once every 4 minutes, and statistically speaking it is unlikely to happen, so you don't tend to see these random fluctuations.
However the built in sensor updates continuously and is updated on the screen every time the screen refreshes - which is at least once a minute (to update the clock) and probably more frequent if updates from other zones are arriving at different times, leading to multiple screen updates per minute so the built in sensor reading has a habit of "toggling" its least significant value if it is right on the threshold because it can update so frequently.
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