I have evohome installed for a good few years and for various reasons it went out of use until I got it set up again in October (~3 months ago). Really all i had to do was replace the batteries and re-bind a couple of zones and everything worked as it should. Our system here has 13 rads with no zoning at all, 12 have HR92s and the one in the hotpress has its valve open all the time. There is one BDR91 controlling the oil boiler. I had support do a firmware update to latest in October.
Everything has been working fine but now the zones batteries seem to be running low and its causing issues. Looking on the HR92 they still show as 2 bars on the battery but will occasionally show the low battery warning on the main controller screen.
The main issue is the zones setting themselves to 20 degrees continuously, the sequence of events for this (making some assumptions):
- Zone receives new temp
- HR92 attempts to change valve position
- The load of the motor causes a voltage dip
- HR92 powers off
- Voltage goes back up
- HR92 powers back up
- HR92 defaults to 20 degrees
- Controller syncs and takes this as a manual override
I guess i have two questions
- Is this correct behaviour following a reset?
- I suspect the problem could be caused by the batteries being fairly cheap ones?