10. OPTIONAL HVAC SET-UP FEATURES
There are a number of HVAC features that can be configured for the particular application.
These include temperature control options, display options and high/low balance points
(heat pumps only).
A) TEMPERATURE CONTROL OPTIONS
1. OFFSET – allows the user to offset the displayed room temperature
±
3°F from true
temperature. This thermostat is calibrated to be within
±
1°F of true temperature.
2. 1ST STAGE DIFFERENTIAL – determines the level of control and consequently the cycle
rate. Adjustable between 0.5°F and 2.0°F, this is the value above/below the set point
that the temperature must rise (fall) to start the cooling (heating). It is also the value
below (above) the set point that the temperature must fall (rise) for the cooling (heating)
to stop. For example, if the temperature setting was 70°F and the 1st stage differential
was set at 0.5°F, in the heat mode the heat would come on at 69.5°F and stay until the
temperature was 70.5°F. A small differential will result in a tighter control, but more
heating/cooling cycles.
3. 2ND STAGE DIFFERENTIAL – again adjustable between 0.5°F and 2.0°F, this also
determines the level of control by determining when to use the 2nd stage of heating or
cooling. It can also be used to keep 2nd stage cooling from coming on too soon when
1st stage is acting to control temperature levels or to keep costly auxiliary heat from
coming on too soon when the heat pump is sufficient.
B) BALANCE POINTS
These values are adjustable, but are only used by the thermostat when it has been
configured to operate as a heat pump and when a remote outdoor temperature sensor,
with address #1, is wired to the thermostat.
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