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by afternoon sun through large windows. When the sun sets, it can take a long time
for the floors to get warm again. This may cause the room to cool off too much in the
early evening. A floor minimum setting can help with this condition by maintaining a
floor minimum temperature. Keep in mind the floor minimum temperature will override
the air temperature, and if set too high, may overheat the room.
A floor maximum is recommended for rooms with hardwood floors. Setting floor minimum
and maximum temperatures is a way of enhancing the comfort of the living space while
protecting floor coverings.
If there are more than one floor temperature sensors, the temperature is averaged.
Cooling Differentials
The first stage cooling turns on when the air temperature rises 1.5°F (1°C) above the
Cool To setting and shuts off when the air temperature reaches the Cool To setting.
The second stage cooling has an adjustable differential and time delay setting to
determine when the stage turns on, and shuts off when it reaches 0.5°F (0.25°C)
above the Cool To setting.
Heat Pump Balance Point
An air source heat pump's Coefficient of Performance (COP) declines with falling
outdoor air temperature. The Balance Point is the outdoor temperature at which it is
more economical to shut off the heat pump (relays Y1 and Y2) and operate the backup
heating equipment (relays W1 and W2).
Dual Fuel
Dual fuel systems include a heat pump together with a backup heat source such as
a furnace or a hydronic fan coil. When Dual Fuel is set to on, the heat pump (relays
Y1 and Y2) is shut off whenever the backup heating equipment (relays W1 and W2)
is operating.
Warm Weather Shut Down (WWSD)
The heating system can automatically shut off based upon the outdoor temperature
and the WWSD setting. This provides a convenient way to shut off the heating system.
Cold Weather Shut Down (CWSD)
The cooling system can automatically shut off based upon the outdoor temperature
and CWSD setting. This prevents unwanted cooling during the winter.
Relative Humidity Sensor
The thermostat includes an internal relative humidity (RH) sensor and has the option
to connect to an external RH sensor. The installer has the option to disable the internal
RH sensor when an external RH sensor is installed. When both the internal and external
RH sensors are enabled, the RH reading is averaged.
Humidifier Operation
The thermostat controls the relative humidity (RH) by operating either the Accessory
1 or Accessory 2 relays. This is an installer configurable setting. When the RH is
below the Humidify To setting by 3%, the Accessory 1 or 2 relay is closed to operate
a humidifier. The humidifier is shut off when the RH reaches the Humidify To setting.
Relative Humidity Operation
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