Auto Changeover Mode; Emergency Heat Mode - Honeywell T10 Pro Smart User Manual

Auto Changeover operation
Auto changeover is available if the thermostat is configured for at least 1 heat stage and 1 cool stage and the installer enabled
auto changeover.
When configured this way, you can select "Auto" as one of the options under "System mode".
When in auto mode, the customer can always set the heat and cool setpoint to the same temperature, regardless of the
differential setting although most customer prefer to have a cool setpoint that is at least 3 degrees above the heat setpoint.
When configured for 0 differential by the installer, we enforce a 1.5°F differential behind the scenes to ensure the heat doesn't
come on after cooling shuts off or vice-versa.
The differential is the minimum number of degrees the temperature needs to rise or fall before switching from heat to cool while
in auto changeover mode. Example: With a 3 degree differential, If heat and cool were both set for 70, and heat had been used
last, the temperature would need to rise at least 3 degrees above the heat setpoint before the thermostat would turn on cooling.
Then it would cycle cooling on and off to maintain setpoint and the temp would need to drop at least 3 degrees below the cool
setpoint before heat could come on.
If the AC is used for dehumidification then we enforce an additional temp drop below the overcooling amount, prior to switching
back to heat.
Em Heat mode
Emergency heat runs when you manually switch the thermostat to the em heat mode. When the thermostat is in emergency heat
mode, the heat pump is locked out. When the thermostat is set to em heat mode, the heat pump is locked out and the backup
heat is used to maintain the heat setpoint.
Emergency heat mode is only available when the thermostat was configured for a heat pump with Backup heat by the installer.
From home screen touch the menu icon and then "system Mode". You can set the thermostat to heat, off, cool, emergency heat,
or auto (auto only available if configured by installer).
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