On 1/16/2015 8:40 AM, trader_4 wrote:
On Thursday, January 15, 2015 at 11:43:12 PM UTC-5, Nil wrote:
On 15 Jan 2015, trader_4 wrote in
alt.home.repair:


Then maybe you can answer another question I've been wondering
about: If I reprogram the times and temps, will I also have to go
through this painful training period all over again? What about if
I lose power?

With regard to changing times and temps, no, it doesn't affect what
it's learned regarding the adaptive recovery. It just learns how
long it takes to raise the temp. It knows that it has to raise it X
degrees. It also knows how fast and how far the temp dropped during
the setback time, how much the furnace had to run, if at all during
the setback period. From that it can calculate how long it's going
to take to get the temp back up.
That's not been my experience with a Honeywell adaptive thermostat. My
experience is that even temporary overrides of a learned program will
require the thermostat to relearn the original program. As an example,
when I want to keep it somewhat warmer than usual on a particular winter
night (guests visiting) and use either the "temporary" feature or the
"hold temp" feature overnight, after resuming the program with "run
program", for the next 3-4 days the furnace will come on at least an
hour earlier in the AM than it would prior to the temporary override,
even though the outside temps are about the same.


Mine were never anywhere near that far off, right out of the
box. They do learn and adjust though based on experience. I
would give it a week and see what happens.
Mine generally takes about 3-4 days to stabilize start time after
changing a setting - either by override or by changing the programmed
setting. However, the more modern models may learn more quickly - my
Honeywell Chronotherm III is more than 10 years old.