Discharge Air Temperature Control Mode - Data Aire gForce Ultra User Manual

 Variable speed compressor C1 starts to ramp down to minimum speed when
return temperature reaches setpoint + 1⁰F.
 Variable speed compressor cycles off at Temperature Setpoint.
 CW Valve will close 10% for every 0.1⁰F below the setpoint plus 1⁰F and
completely close at setpoint.
 Compressor will not violate its minimum runtime.
* This applies on dual compressor system.

9.2.2 Discharge Air Temperature Control Mode

9.2.2.1 Single DX circuit - One variable speed compressor system
 Compressor settings type in dap4™ Factory Settings menu is programmed to
"Var. Sp" and Control mode is set to "Supply".
 There is a five (5) minute delay between start-to-start of the compressor. The
delay will be increased to six (6) minutes for one (1) hour following the detection
of a short-cycle condition even if the short cycle alarm is disabled using a short
cycle alarm menu.
 There is a two (2) minute delay between stop-to-start of the compressor.

Once compressor C1 comes on, it must remain on for a minimum runtime even
setpoint satisfies.
 If variable speed compressor C1 runs at the minimum speed for a period of time,
it will automatically ramp up to the maximum speed for one minute to maintain
the minimum compressor oil level. The temperature may drop slightly during this
override period.
 Compressor cycles on and modulate as follows:
Discharge air temperature is rising (On cycle):
 When discharge air temperature rises to Temperature Setpoint + Temperature
DB (deadband), variable speed compressor C1 will start and operate at its
minimum speed.
 dap4™ will then use PID (proportional-Integral- derivative) control logic to
modulate the variable speed compressor C1 to maintain temperature setpoint.
PID values are programmed in Factory settings menu.
10-2014 gForce User Manual ● 107