BAS-SVX36C-EN
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Operational and Programming Reference Information
This section provides additional information that may be useful for understanding thermostat
operation or programming.
Deadband
The thermostat automatically maintains a temperature deadband between the heating setpoint
and the cooling setpoint whenever automatic changeover (heat-to-cool or cool-to-heat mode) is
enabled. The temperature range of the deadband is 2–9 °F (1.0–4.5°C) and is specified in the
installation configuration options (see
“Configuration,” p. 26
). If you attempt to change a
temperature setpoint to within the deadband of its opposing setpoint, the opposing setpoint will
automatically be pushed to the next value that satisfies the deadband. (See
Figure 38
.)
Heat and Cool Cycling Rate
The heat and cool cycling rate, expressed in cycles per hour (CPH) indicates how often heating or
cooling system is turned on when temperature is within the temperature differential from the
setpoint, which is 1°F (0.5°C).There are ten options (1–10) for heat stages and five options (1–5) for
cool stages. The number selected is the maximum number of times the stage is cycled in 1 hr.
For example, when the system is set to 5 CPH, it runs at 12 min cycles with variable duty cycle.
Depending on the heating or cooling load, which is measured by feedback from the sensor
thermistor and/or temperature error, the system could run at 50% duty cycle (6 min ON and 6 min
OFF), 80% duty cycle (9.6 min ON and 2.4 min OFF), or other variations of the duty cycle.
Note:
The cycling rate described above is only active when the temperature is within the
temperature differential. If the temperature is outside of the temperature, the heating and
cooling equipment will either be fully on or fully off accordingly. (See
Figure 38
.)
Figure 38. General Heat and Cool Cycling Rate Diagram
There is one cycling rate setting for each of the thermostat’s available heat and cool stages,
including auxiliary and emergency heat stages. You can specify them during installation
configuration. See
“Configuration,” p. 26
.
Minimum Compressor Off Time
To protect the compressor from cycling too frequently, there is an automatic 5 min gap between
cycles. You cannot reduce the gap, but you can add up to 5 min if needed. See
“Configuration,”
p. 26
.
All heat
stages on
TD
0 %
100 %
TD
TD
TD
All heat stages
cycling dependent
on load
All heat and cool
stages off
All cool stages
cycling dependent
on load
All cool
stages on
Heat set point
temperature differential
(TD) is ±1°F (0.5°C)
centered on set point
Cool set point
temperature differential
(TD) is ±1°F (0.5°C)
centered on set point
Temperature
Output
Adjustable deadband
2–9°F (1–4.5°C)
