Data Aire gForce Ultra - Page 116

116 ● gForce Ultra User Manual 10-2014
9.4.2.2 Dual DX circuit with a variable speed compressor and a fixed speed compressor
Dehumidification cycles on – dewpoint is rising
 If unit is not in cooling mode, If dewpoint continues to rise, the variable speed
compressor will turns on when Dewpoint = High Dewpoint SP - 1⁰F and operates
at minimum speed (0V) then modulates from 0% to 100% in 0.1% increment if
dewpoint rises to high dewpoint setpoint. For instance:
 If Dewpoint = High Dewpoint SP – 1⁰F, compressor will run at 0% (0VDC)
 If Dewpoint = High Dewpoint SP – 0.9⁰F, compressor will run at 10% (1V)
 If Dewpoint = High Dewpoint SP – 0.8⁰F, compressor will run at 20% (2V), etc.
 C2 fixed speed compressor will cycle on when Dewpoint = High Dewpoint
Setpoint.
 If space is overcool, reheat will come on based on temperature setpoint and C2
compressor will turn off. C1 variable speed compressor will continue to operate
until dewpoint drops below High Dewpoint Setpoint – High Dewpoint Deadband -
1⁰F but not to violate the dehumidification inhibit logic (In limit/ No limit) stated
above.
 If cooling is on during dehumidification cycle and dehumidification mode is set to
“2C in Limit” or “1C in Limit”, the temperature cooling control will override the
Dewpoint Control. If dehumidification mode is set to “1C No Limit” or “2C No
Limit” the unit will continue to finish the dewpoint control cycle then reverse to
the temperature control.
Dehumidification cycles off- dewpoint is dropping
 C2 fixed speed compressor (NO3) will turn off when Dewpoint = High Dewpoint
Setpoint – High Dewpoint Deadband.
 Variable speed compressor C1 starts to ramp down in 0.1 % decrement when
dewpoint drops below High Dewpoint Setpoint – High Dewpoint Deadband.
 C1 compressor will run at minimum speed when Dewpoint = High Dewpoint SP-
Dewpoint Deadband - 1⁰F.
 C1 compressor turn off (NO2) when Dewpoint = High Dewpoint SP – Dewpoint
Deadband - 1.5⁰F and variable speed compressor minimum runtime has expired.
9.4.2.3 High Relative humidity Limit in dewpoint control
 If high relative humidity condition occurs while humidity control mode is set to
Dewpoint Control then Dewpoint Control has priority over the Relative Humidity
Control.