Need help with temperature sensor setup

[JoeJ]

I have a Zooz ZSE44 temperature/humidity sensor. I want to set this up so that I can keep a
small studio building from freezing, My plan is to turn on a heater if the temperature drops below 45F.

I initially used RM to set a trigger event that if the temperature drops below 45F, to use another Z-wave switch to turn on a heater in the building.

Seems simple enough to set up, but I have some questions. How often does the C7 check the temperature? Is this set by the "Temperature Reporting Interval" in the driver? If not, I'm concerned about waking the sensor up too often due to being a battery device. Secondly, what about hysteresis? If the temperature is right at 45F will the heater toggle on and off excessively?

Thanks for your answers. I'm still new at this.

[Ranchitat]

Have a look:

[RELEASE] Advanced vThermostat - Virtual Thermostat HVAC control

Advanced vThermostat is a Hubitat Device Type Handler that will help create a proper virtual thermostat device. It is meant for use with dumb space heaters / air conditioners and make them controllable via Hubitat just like a regular electronic Thermostat would. It is based on vThermostat by Josh208 that seems to be MIA from the Hubitat community. Originally ported from the SmartThings-VirtualThermostat-WithDTH. This device handler allows the creation of a new Device that shows as a thermosta…

[brad5]

Technically the C7 doesn't actually check the temperature. The Zooz reports the temperature to the C7. That interval is determined by the device settings, which usually can be manipulated by the device driver itself. I'm not familiar with the ZSE44 but from looking at the driver it appears you can manipulate both the reporting threshold (sensitivity to temperature change) and the interval.

To your point the frequency of reporting will affect battery life so you have to balance that with what is practical for your application. I think every 5 min or so should be sufficient and not drain your batteries too much, but you may find that a longer reporting interval works just as well.

I do something similar with humidity sensors and a dehumidifier. I have the dehumidifier turn on at 55% and off at 50%. This tends to eliminate the rapid toggling you mention.

RM will work fine for this app and it's not all that complicated to do, but you could also use the advanced virtual thermostat manager community-supported app. It does pretty much what you want.

[kahn-hubitat]

@JoeJ

Seems simple enough to set up, but I have some questions. How often does the C7 check the temperature? Is this set by the "Temperature Reporting Interval" in the driver? If not, I'm concerned about waking the sensor up too often due to being a battery device. Secondly, what about hysteresis? If the temperature is right at 45F will the heater toggle on and off excessively?

Thanks for your answers. I'm still new at this.

there are 2 settings in the driver that affexts this

1. temperature change trigger.. will trigger an event when the temperature changes this amount
2. and the one you alude 2 temperature reporting invterval. if another event has not come in will report this often.

if you want it to trigger at 45 you can use <= instead of < in your trigger event.

it wont trigger excessively if you set the change trigger to be say one degree. i use .5 degree and mine does not trigger excessively.. if you are worried you can use the "and stays" option in rule machine on your temp trigger and say it stays <= to your temp say for 5 minutes. etc.

hope this helps