McQuay MicroTech III RAH, Operation And Maintenance Manual, Page: 41 / 122

McQuay OM 920-1 41
Keypad/Display Menu Structure
Dehumidification Setup Menu
RH DB is an adjustable item that sets a dead band around the relative humidity set point. For
example, if the RH Setpoint parameter is set to 50% and the RH Db parameter is set to 2% the
dead band around the set point would be from 49% to 51%.
Dewpoint DB is an adjustable item that sets a dead band around the dew point set point. For
example, if the DewPoint Spt parameter is set to 50ºF and the DewPntDb parameter is set to
2ºF the dead band around the set point would be from 49ºF to 51ºF.
RH Period is an adjustable item which sets the “sampling time” used in the PI control
function for controlling the reheat valve.
RH Gain is an adjustable item which sets the “proportional band” used in the PI control
function for controlling the reheat valve.
RH PAT is an adjustable item which sets the “project ahead” used in the PI control function
for controlling the reheat valve.
RH Max Chg an adjustable item that sets the maximum value for an increase or decrease for
controlling the reheat valve.
RH Stg Time is an adjustable item is an adjustable item which sets a stage time period
between the minimum and maximum cooling stages during dehumidification operation.
Stg Rht DB is an adjustable item used for reheat control when unit is configured for 1 stage
hot gas reheat control.
Dehum Method is an adjustable item used to select whether dehumidification operation is
based on relative humidity or dew point.
Dehum Ctrl is an adjustable item used to select whether dehumidification as “always”
allowed or only during “occupied” modes of operation.
Table 36: Dehumidification Setup Menu
Menu Display Name Item Display Name Default Setting Range Password Level
Dehum Setup RH DB= 2% 0-10% 4
Dewpoint DB= 2°F 2-10°F 4
Reheat Period= 10s 0-999s 4
Reheat Gain= 1 0.0-100.0 4
Reheat PAT= 20s 0-999s 4
RH Max Chg= 16% 0-100% 4
RH Stg Time= 10 0-60m 4
Stg Rht DB= 5°F 0-20°F 4
Dehum Method= None None 4
Rel Hum
DewPt
Dehum Ctrl= Occupied Occupied 4
Always
Sensor Loc= Return Return 4
Space
OAT
Mn Lvg Coil T= 48.0°F - 4
Mx Lvg Coil T= 55.0°F - 4
Min Rheat Spt= 55.0°F 40.0-100.0°F 4
Max Rheat Spt = 65.0°F 40.0-100.0°F 4
RH Sens Type= VDC VDC 4
mA
RH Min Signal= 0.0V 0.0-20.0 4
V/mA
RH Max Signal= 10.0V 0.0-20.0 4
V/mA
Min Dehum Spd= 33% 0-100% 4
Max Dehum Spd= 100% 0-100% 4
Rht Min Pos= 10% 0-100% 4
Rht Dec Rate= 1.00%/s 0-10%/s 4