Centralite Pearl Thermostat


Are you referring to the hysteresis?, if so its not in the driver, and I haven't specifically dig into every single attribute in the thermostat cluster to see if it's in there or not.


Look here: Centralite Pearl - change hysteresis settings?

Somebody changed it via the settings at the thermostat and said it worked. But you can apparently only go down to 1 degree from 1.8 degrees.


From my experience, 1 degree F is the lowest most thermostats will go on that setting.

In fact, I'm not sure I've ever seen a thermostat that would go lower than that... I'm sure there are some out there somewhere, but I've never seen one in residential service.


Thanks @denise.grider! I had that manual but totally missed the "Deadband" parameter. The Honeywell thermostat that I replaced called it "Swing" temperature. With your help, I'm tweaking it now. Lol, I didn't realize so many others had the same issue. Thanks again, -Joel


The Radio Thermostat CT100 and related allow for a setting of .5 degrees.


Interesting. That is a new data point I didn't know. Thanks!

Not sure how useful that really is, but I stand corrected.


For me, it was useful in giving more control to calibrate all the temperature reading devices in my home. I've have several postings here (including graphs) regarding my journeys in trying all the devices as close as possible. I've managed to get my thermostat (a CT101) within .4 degrees of 5 wirelesstag temp sensors and having that .5 helped.


But this setting is only what delta temp VS setpoint it turns on/off at... Not sure how that has anything to do with calibration.

But in any case, if it is useful for you, great. Just keep in mind if you ever switch thermostats, MOST do not allow < 1 DegF swing setting as it will cycle on/off the HVAC a potentially disturbingly high number of times (not good for the equipment at all, especially if there aren't proper min runtime and min off time settings in the thermostat or zone controller [if present]).


It helped the calibration process by narrowing with window when the HVAC would turn on/off. I could then set different heating or cooling points and get an average from the tags.

Fortunately I'm doing this in winter and the cycling isn't creating much havoc with it. I certainly wouldn't do it during the summer as I wouldn't want to blow up the compressor.


Anyone ever had issues with the Pearl not responding to the FanAuto command? I am having issues trying to set that from rule machine on one of my rules.
What I am trying to do is have the fan run for 5-10min every hour. I have a periodic trigger that turns the fan on ok, but my trigger to set the fan back to auto does not work. The rule says it sent it, but the Pearl log shows no response.



I have had no issues whatsoever. I run the fan every three hours if there hasn't been a heating or cooling cycle recently.


Thanks! I will try this, it is cleaner than what I was doing.


Thanks!, works great, I think mine was overthought.