Daikin DPS Installation And Maintenance Manual page 50

Microtech iii unit controller for rebel commercial packaged rooftop systems
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Htg Stage Time is an adjustable item used to set a minimum
time period between heating stage changes .
Htg DB is an adjustable item which sets a dead band around
the discharge heating set point parameter . For example, if the
discharge heating set point parameter is set to 100ºF and the
Htg DB= parameter is set to 2ºF, the dead band around the set
point would be from 101 .0ºF to 99 .0ºF .
Htg Period an adjustable item which sets the "sampling time"
used in the PI control function that modulates the heating valve
or face & bypass dampers .
Htg Gain is an adjustable item which sets the "Gain" used in
the PI control function that modulates the heating valve or face
& bypass dampers .
Htg PAT is an adjustable item which sets the "project ahead
time" used in the PI control function that modulates the heating
valve or face & bypass dampers .
Htg Max Chg is an adjustable item that sets the maximum
value for an increase or decrease of the heating valve or face
& bypass damper position .
Htg Lo OAT Lk is an adjustable item that sets a low outdoor
ambient temperature value below which compressor heating is
locked out .
Htg Hi OAT Lk is an adjustable item that sets a high outdoor
ambient temperature value above which compressor heating is
locked out .
EffHtgOATLk is a status only item that displays the current
value that is being used for high outdoor ambient compressor
heating lock out . Normally this value reads the same as the Htg
Hi OAT Lk but can be lower due to the low differential pressure
limiting function while the unit is operating in the Heating or
MinDAT states .
SuplHtg Hi OAT Lk is an adjustable item that sets a high
outdoor ambient temperature value above which supplemental
heating is locked out .
OAT Diff is an adjustable item which sets a differential below
the OATHtg Lock parameter . Heating operation is re-enabled
when the outdoor air temperature sensor input falls below the
OATHtg Lock value by more than this differential .
Htg Reset is an adjustable item used to set the type of heating
reset to be used .
Min Htg Spt is an adjustable item which sets the minimum
heating discharge set point for use with a heating discharge air
temperature set point reset schedule .
Min Htg Spt @ is an adjustable item which sets the value of
the sensor input, selected with the heating reset parameter, at
which the heating set point is reset to the Min Htg Spt value .
OM 1141-3 • MICROTECH UNIT CONTROLLER
Max Htg Spt is an adjustable item which sets the maximum
heating discharge set point for use with a heating discharge air
temperature set point reset schedule .
Max Htg Spt @ is an adjustable item which sets the value of
the sensor input, selected with the heating reset parameter, at
which the heating set point is reset to the Max Htg Spt value .
Min DAT Ctrl is an adjustable item used on VAV or CAV
discharge control units to activate or deactivate the low
discharge temperature limit function available on units
equipped with modulating or multistage heat .
Min DAT Limit is a status only item which indicates the
discharge air low limit temperature on CAV zone control
units . Heating will be activated to maintain this setting when
the discharge temperature falls below it during the Fan Only
operating state . On VAV or CAV discharge control units, the
minimum discharge temperature limit is the DAT Clg Spt .
Occ Heating is an adjustable item which enables and disables
the "daytime" heating mode of operation . If the Occ Heating
parameter is set to No, the unit will only go into heating during
the initial morning warm-up cycle . If the Occ Heating parameter
is set to Yes, the unit can go into the heating mode of operation
any time during the day .
Unocc Diff is an adjustable item that sets the unoccupied
heating differential .
Htg Warmup Tm is an adjustable item which is used to set the
amount of time the gas burner will remain at a low fire position
on 100% OSA units (default 60 seconds) during the special
cold start sequence .
Htg Hld Period is an adjustable item used to set the amount
of time that the gas heating valve remains at its calculated
value on units equipped with 100% OA (default 240 seconds)
during the special cold start sequence . This is to allow the
temperature to approach equilibrium with the modulating gas
heating valve at a fixed position.
MWU Sensor is an adjustable item that sets the temperature
sensor input to be used for morning warmup heating operation
on discharge air control units . Setting this parameter disables
morning warm up operation .
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