Applications Guide Tracer Graphical Programming - Trane
Applications Guide Tracer Graphical Programming - Trane
Applications Guide Tracer Graphical Programming - Trane
You also want an ePaper? Increase the reach of your titles
YUMPU automatically turns print PDFs into web optimized ePapers that Google loves.
®<br />
Reviewing the sequence of operation<br />
Control<br />
The following parameters for the sequence of operation are presented<br />
according to the equipment that must be controlled.<br />
Supply fan<br />
Operate the supply fan continuously whenever the air handler is in occupied<br />
or night heat/cool modes. Turn the supply fan off whenever one of the<br />
following occurs:<br />
• The air handler is unoccupied.<br />
• The run/stop interlock is open.<br />
• The mixed air temperature is too cold, and the low limit detection is<br />
closed.<br />
• The supply fan status indicates a fan failure after a 1-minute delay.<br />
Note:<br />
Afailureduetolowmixedairtemperatureorfanfailure<br />
requires a manual reset. Also, the low limit switch may require<br />
a manual, hardware reset.<br />
Outdoor air damper<br />
When the economizer function is enabled and the outdoor air temperature<br />
is less than the economizer changeover setpoint, modulate the outdoor<br />
air damper between the adjustable minimum position and fully open<br />
to maintain the discharge air cooling setpoint. Modulate the outdoor air<br />
damper closed, overriding the minimum position, to maintain the mixed<br />
air temperature at or above the mixed air setpoint.<br />
If the economizer function is disabled or the air handler is in the heat<br />
mode, control the outdoor air damper to its minimum position. If the outdoor<br />
air temperature falls below a low ambient damper lockout setpoint,<br />
control the outdoor air damper to its closed position. In unoccupied mode,<br />
control the outdoor air damper to its closed position. Also, if the supply<br />
fan is off or the mixed air temperature sensor is failed, control the outdoor<br />
air damper to its closed position.<br />
Exhaust fan<br />
Coordinate exhaust fan operation with the unit supply fan and outdoor<br />
air damper position. Energize the exhaust fan whenever the supply fan is<br />
on and the outdoor air damper is open beyond 30%. Keep the exhaust fan<br />
on until the outdoor air damper closes to below 20% open or the supply<br />
fan is turned off.<br />
Cooling valve<br />
Modulate the cooling valve to maintain the discharge air temperature at<br />
the discharge air cooling setpoint. If the economizer function is enabled<br />
and the outdoor air damper is not open at least 90%, control the cooling<br />
valve to its closed position. Also, close the cooling valve if the air handler<br />
CNT-APG001-EN 193
Change language