Daikin One+ Reference Manual page 41

Heat Pump as Primary Heat Source (con't)
T on and T off provide an alternative control method to have the
»
thermostat control the aux heat source using its PI control algorithm.
» Heat pump lockout is adjustable from -20°F to 65°F in 5°F
increments. (required, default 15°F)
» Aux heat lockout is adjustable from -10°F to 75°F in 5°F increments.
(optional, default 50°F)
» Aux heat demand
– T on and T off based control of aux heat demand allows for the
following ranges:
– T on differential: -7°F to 3°F in 1°F increments (default 3°F)
– T off differential: -4°F to 1°F in 1°F increments (default 1°F)
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