Thermostat: Heating shown as switched on but is not. It switches on only when setting temp 2 degrees above current temp


My Wyze Thermostat often tells me that heating is on when it’s not. As an example, I would set the target temperature to 65 degrees, The current temperature might be shown as 58 and the Thermostat says that it’s heating up, but it isn’t. The only way I can get force the heat to run is to set the target temperature to 2 degrees above (e.g., 60). Then the heater wold kick off, The problem of course is that I then become a human thermostat, having to manually manage everything.

Any help would be appreciated.

In case it helps, here’s my wiring:


From your description, it sounds like w2 isn’t actually working. Try disconnecting the w2 wire from the wyze and resetting it, and during setup tell it the “old” thermostat doesn’t have a W2 wire.

I am not an HVAC guy so I can’t tell you anything about the wiring or if it is wrong or right…

That being said. My thermostat acted a little different than my old thermostat as well and I had to fiddle with the settings to get it to act right.

When the thermostat says its heating but the fan is not running, mine is in “pre-heat mode”. It is warming up and getting ready to blow. I had to change the setting in the Advanced Settings to 15 seconds. 15 seconds after the thermostat clicks and indicates heat or cool, then the fan kicks in. Check your HVAC unit manual for the manufacturer’s recommendation. But, I had the same thought…why isn’t it running? There is also a place to adjust the Differential Temp. The 2 degrees you mentioned seems to be the default setting. My heat would only kick in if it got 2 degrees below the set temp and stop 2 degrees above. AC started when the temp registered 2 degrees above my set point and stopped 2 degrees below. I dropped mine down to 1 degree so now, set on 66, it kicks in at 65 and out at 67. The differential temp is to save energy. It uses less energy to heat or cool 4 degrees a couple of times than it does to heat or cool 2 degrees a bunch of times. The narrower the differential, the more times the system starts and runs. Most energy usage is in the startup. Also, if the temp is not reading accurate to the true temp, you can adjust that by adjusting the Temperature Correction. Mine was 1 degree off from true temp.

Good luck. Hope this helps!

EDIT: I don’t have emergency heat on my Gas Package Unit…I live south of the Mason Dixon Line. If you have Emergency Heat it changes everything and someone else with more knowledge will need to chime in.

Also, just found this courtesy of @Jason-L on the Thermostat User Survey Thread. Thanks Jason!

Thank you for the help @speadie and @SlabSlayer
Your suggestions helped me understand what the issue might be, most importantly, that W2 was possibly related to the issue. I measured voltage between W2 and C (~24V) which confirmed that W2 should work. I therefore guessed that I might need to repeat the entire setup process. Now that I have, things seem to be working fine. Perhaps the previous config was somehow incorrect and that’s why W2 wasn’t being triggered.

Thanks again!