That reminds me of an argument that I had with the gas man who last came to service the boiler. He insisted that, as the thermostat showed a low battery warning, that it would soon start to malfunction and I should treat this as urgent.Interesting, though I think I'm coming to the same conclusion as Ken. For some reason I have had to replace the 2 AA batteries in the central heating timer/thermostat 3 times already since we moved in February!
What I have observed is completely explained by this chart from up the thread:Note at the left of the graph there is a decline from the "fully charged" voltage to the nominal 1.2V that the cell will have for the most of the time. The thermostat manufacturer seems to have put their low batter threshold right in that region, so if I put a pair of freshly charged cells in it, it doesn't show the low battery alert initially. I haven't timed how long it takes to appear, but maybe a couple of weeks or a month. Then the thermostat will work for a long time, I think at least a year, before the battery actually needs to be changed.
Statistics: Posted by Coeus — Tue Dec 31, 2024 9:16 pm