Reznor RCB User manual

Form CP-MAPSIII-D19, Doc No 303069, Page 1

Form CP-MAPSIII-D19 (09-15)
Applies to: Models RCB, RDB, RECB, REDB, RDCB, RDDB
Module Air Processing Systems (MAPS III) Manual for Option D19 Makeup Air Control
Example of Remote Controller Display (Option RB5 or RB6) Key Symbols
Function Key Identication Alarm Prg Esc Up Enter Down
Function Key Display on the
Remote Controller
1.1 Display Function
Keys
The control system utilizes a factory installed remote display which allows for complete access to unit test features, schedules,
discharge air setpoints, fan control, alarms, and other unit operational setpoints. The control features include:
• Local and remote alarming
• Integrated time clock
• Compressor anti-cycle protection and minimum “on/off”
cycle rates
• Multiple protocol support [BACnet® (MSTP) or LonWorks®]
• Alarm shutdown feature
• Commissioning and test mode functions
• Optional wall mounted or handheld remote display
• Energy conscious applications
• TAB menu for creating a backup of setpoints
1.0 Digital
Controller
1.0 Digital Controller............................................1
1.1 Display Function Keys...................................1
1.2 Controller hardware input – output points .....3
2.0 Sequence of Operation .................................4
2.1 States of Operation .......................................4
2.2 External Contacts Description
(ID4 Through ID8) .........................................4
3.0 Controls..........................................................6
3.1 Supply Fan Control .......................................6
3.2 Intake Damper Control ..................................6
3.3 Temperature And Humidity Control ...............8
3.4 Heating Control .............................................9
3.5 Cooling Control............................................10
3.6Dehumidication..........................................10
4.0 Safeties and Alarms .................................... 11
4.1 Alarms ......................................................... 11
4.2 Alarm Management .....................................13
5.0 Start Up.........................................................15
5.1 Set the Date and Time on the Controller Clock 15
5.2 Setting the Unit for Operation with the D19 Control
Sequence ....................................................15
5.3 Unit Test Mode
....................................................................16
6.0 Controller History Log.................................20
7.0 Controller Display Menus ...........................21
8.0 Communication Cards ................................29
8.1 BACnet®MSTP (Option BHB8) Communication
29
8.2 LonWorks®(Option BHB7) Communication 33
Index ...................................................................36
Table of Contents

Form CP-MAPSIII-D19, Doc No 303069, Page 2
1.0 Digital Controller (cont’d)
1 2 3 4 5 6 7 8
ON
1 2 3 4 5 6 7 8
ON
RETURN AIR DIP SWITCH
POSITIONS 1 & 7 “ON”
EXHAUST DIP SWITCH
POSITION 7 “ON”
ADDRESS 128
RETURN AIR TEMP & HUMIDITY
SENSOR
ADDRESS 129
EXHAUST AIR TEMP & HUMIDITY
SENSOR
Exhaust Air / Return Air
Temp & Humidity Sensor
Addressable Dip Switch
Settings: Factory set when
ordered on new production
units.Forretrotstheuser
must set the addresses
accordinglyintheeld.
Optional Exhaust Air / Return Air Temp & Humidity Sensors:
These sensors are duct mount style and operate on a RS-485 communication trunk.
Note: Refer to the Installation
manual and or unit wiring
drawingsforspecicwiring
information.

Form CP-MAPSIII-D19, Doc No 303069, Page 3
1.2 Controller hardware input – output points
Input
Terminal
Input Point
Name Input Description Signal type Signal Range Always Active
U1 OA_Hum_Raw Outside Air Humidity 0 -10 Vdc 0 to 100% RH x
U2 OA_Temp_Raw Outside Air Temp Thermistor 10K-2 -35 °F to 240 °F (-37°C to 115°C) x
U3 Ext_Dmpr_Cmd External Unit Damper Command 0 -10 Vdc 0 to 100%
U4 DA_Temp Discharge Air Temp Thermistor 10K-2 -35 °F to 240 °F (-37°C to 115°C) x
U5 CC_Temp Cooling Coil Discharge Air Temp Thermistor 10K-2 -35 °F to 240 °F (-37°C to 115°C) x
U6 MA_Temp Mixed Air Temp Thermistor 10K-2 -35 °F to 240 °F (-37°C to 115°C) x
U7 Bldg_Pressure Building Static Pressure 0 - 10 Vdc -0.5” iwc thru + 0.5”iwc
U8 Duct_Pressure Duct Static Pressure 0 - 10 Vdc 0 - 2.5” iwc
U9 Spc_CO2 Space CO20 - 10 Vdc 0 - 2,000 ppm
J26
FB2
RA_Temp Return Air Temp RS-485
Communication
RA_Humidity Return Air Humidity
J26
FB2
EA_Temp Exhaust Air Temp RS-485
Communication
EA_Humidity Exhaust Air Humidity
ID1 SF_Sts Supply Fan Status Dry Contact Open = “OFF” / Close = “ON” x
ID2 Filter_Sts Main or ERV Dirty Filter Status Dry Contact Open = “OFF” / Close = “ON”
ID3 Safety_Sts Safety Input Status Dry Contact Open = “ALARM” / Close = “NORMAL” x
ID4 Ext_OCC Occupied Mode Input Dry Contact Open = “OFF” / Close = “ON”
ID5 Ext_Call_Fan External Fan Call Input (G) Dry Contact Open = “OFF” / Close = “ON”
ID6 Ext_Call_Heat External Heat Call Input (W1) Dry Contact Open = “OFF” / Close = “ON”
ID7 Ext_Call_Cool External Cool Call Input (Y1) Dry Contact Open = “OFF” / Close = “ON”
ID8 Ext_Call_Dh External Dehum Call Input Dry Contact Open = “OFF” / Close = “ON”
ID9 Ext_ Switch_1 External Damper Position Sw 1 Dry Contact Open = “OFF” / Close = “ON”
ID10 Ext_ Switch_2 External Damper Position Sw 2 Dry Contact Open = “OFF” / Close = “ON”
ID14 Phase_Alarm Phase Protection Alarm Dry Contact Open = “OFF” / Close = “ON”
ID15 Htr_1_Sts Gas Heater 1 Status Rib Relay N.O.
Contact Open = “OFF” / Close = “ON”
ID16 Htr_2_Sts Gas Heater 2 Status Rib Relay N.O.
Contact Open = “OFF” / Close = “ON”
Output
Terminal Output Point Name Output Description Signal / Range Signal Range Always Enabled
Y1 Damper_Cmd Damper Output Command 0 – 10Vdc 0 – 100% Open x
Y2 SF_VFD_Cmd Supply Fan VFD Command 0 – 10Vdc 0 – 100% Flow
Y3 HX1_Mod_Cmd Gas Heating 1 Modulation Command 2 – 10Vdc 0 – 100% Capacity
Electric Heating Modulation Command 0 – 10Vdc 0 – 100% Capacity
Y4 HX2_Mod_Cmd Gas Heating 2 Modulation Command 2 – 10Vdc 0 – 100% Capacity
Y5 RH_Mod_Cmd Reheat Modulation Command 0 – 10Vdc 0 – 100% Capacity
NO1 SF_Cmd Supply Fan Command 24Vac Contact Open = “OFF” / Close = “ON” x
NO2 Comp_Stg1_Cmd Compressor Stage 1 Command 24Vac Contact Open = “OFF” / Close = “ON” x
NO3 Comp_Stg2_Cmd Compressor Stage 2 Command 24Vac Contact Open = “OFF” / Close = “ON”
NO4 Comp_Stg3_Cmd Compressor Stage 3 Command 24Vac Contact Open = “OFF” / Close = “ON”
NO5 Comp_Stg4_Cmd Compressor Stage 4 Command 24Vac Contact Open = “OFF” / Close = “ON”
NO7 Alm_Rly_Cmd Unit General Alarm Relay Command 24Vac Contact Open = “OFF” / Close = “ON” x
NO8 HX_Stg1_Cmd Heating Stage 1 Command 24Vac Contact Open = “OFF” / Close = “ON”
NO9 HX_Stg2_Cmd Heating Stage 2 Command 24Vac Contact Open = “OFF” / Close = “ON”
NO10 HX_Stg3_Cmd Heating Stage 3 Command 24Vac Contact Open = “OFF” / Close = “ON”
NO11 HX_Stg4_Cmd Heating Stage 4 Command 24Vac Contact Open = “OFF” / Close = “ON”
NO12 HX_Stg5_Cmd Heating Stage 5 Command 24Vac Contact Open = “OFF” / Close = “ON
NO13 HX_Stg6_Cmd Heating Stage 6 Command 24Vac Contact Open = “OFF” / Close = “ON”
NO17 RH_Cmd Reheat compressor Command 24Vac Contact Open = “OFF” / Close = “ON”

Form CP-MAPSIII-D19, Doc No 303069, Page 4
2.0 Sequence of
Operation
The control system operates the supply fan, exhaust fan, intake dampers energy
recovery, DX cooling, and gas/electric heat to maintain a set of discharge air tempera-
ture control setpoints.
The unit discharge air temperatures fall within the following three categories
1. Unit supplies Neutral air temperature that does not affect space conditions.
2. Unit supplies Cold air temperature to provide space cooling.
3. Unit supplies Hot air temperature to provide space heating.
NOTE: Heating applies only when a unit is ordered with a gas or electric heat sec-
tion. Heating is included in all control instructions.
The unit operates in the following states of operation:
1. Enable ON
 Theunitispermittedtooperatebaseduponeldsuppliedcontactclosures.The
unit will only switch to the Enable ON state when the state is manually selected
through the user interface device, unit display, or building automation network
communication point.
2. Enable OFF
The unit supply fan and all associated mechanical equipment is OFF in this state.
There are no associated sequences of operation in this state. The unit will only
switch to the OFF state when the state is manually selected through the user
interface device, unit display, or building automation network communication point.
Mechanical System Selections are only permitted in the Enable OFF State.
3. Enable OFF / Alarm
The Enable OFF / Alarm state can only occur from a sequence “failure”. The unit
will stop all mechanical operation until the “failure” condition(s) are resolved. Upon
resolving the failure, the unit will return to its externally commanded condition.
Alarms can also be cleared by resetting power to the unit.
Theunitwilloperatebaseduponthefollowingeld-suppliedcontactclosures:
1. Occupied Contacts (ID4)
When the occupied contacts are closed, the unit will be considered in the occupied
mode. The Dampers, Exhaust Fan, and ERV will follow the occupied mode
sequence. When the contacts are open, the Dampers, Exhaust Fan, and ERV
will operate in the unoccupied mode sequence. There are no other time clock
or schedule functions associated with the unit. (See the damper control section,
Paragraph3.2,forspecicdetails.)
2. Fan Contacts (ID5)
The unit supply fan will be on whenever the supply fan contacts are closed.
The fan will also automatically start whenever the heating, cooling or
dehumidicationcontactsareclosed,otherwisethefanwillbeOFF.Theauto
sequence can be activated from the fan control when the mechanical cooling and
heating contacts are open. For continuous supply fan operation the ID5 contacts
need to remain closed.
3. Heating Contacts (ID6)
Whenever the contacts are closed, the supply fan will start and the heating
sequence will be enabled. Mechanical heat will operate to maintain the following
heating discharge air temperature setpoint.
Unit Discharge Setpoints
# State Discharge Air
Control Variable Default Setpoint
Setpoint
Range
1Heating
Contacts
Space Heating Air
Temperature DA_SpcHtg_SP 90°F (32°C)
50 -140°F
(10 - 60°C)
The unit will not automatically switch to other states except Unit Alarm. When
the contacts are open, the heat and supply fan will turn OFF or operate in
auto-sequence.
2.1 States of
Operation
2.2 External
Contacts
Description
(ID4 Through
ID8)

Form CP-MAPSIII-D19, Doc No 303069, Page 5
2.0 Sequence of Operation (Cont’d)
4. Cooling Contacts (ID7)
Whenever the cooling contacts are closed, the supply fan will start. The
mechanical cooling will operate to maintain the unit discharge air temperature
setpoint.
Unit Discharge Setpoints
# State Discharge Air
Control Variable Default Septoint Range
1Cooling
Contacts
Space Cooling Air
Temperature DA_SpcClg_SP 55°F (12°C)
50 -100°F
(10 - 37°C)
The unit will not automatically switch to other states except Unit alarm. When
the contacts are open, the cool and supply fan will turn OFF or operate in
auto-sequence.
5. Dehumidication Contacts (ID8)
When the contacts are closed and the cooling and heating contacts are open, the
supply fan will start and the unit reheat system will be active.
6. Auto Sequence
When the Fan contacts are closed and the mechanical cooling, heating, and
dehumidicationcontactsareopen,theunitwilloperateintheautosequence.
The unit will operate to maintain the following discharge air temperature setpoints.
If both heating and cooling contacts are enabled, the unit will not turn on any
mechanical system until the condition is removed.
Unit Discharge Setpoints
# State OAT
Allowed
Discharge Air
Control Variable Default Septoint Range
1Auto Sequence
Cool MAT > 65F Neutral Air Temperature DA_NAClg_SP 75°F (24°C)
50 -100°F
(10 - 37°C)
2Auto Sequence
Heat MAT < 65F Neutral Air Temperature DA_NAHtg_SP 65°F (18°C)
50 -140°F
(20 - 60°C)
If both heating and cooling contacts are enabled, the unit will not turn on any
mechanical system until the condition is removed.
2.0 Sequence of
Operation
(Cont’d)
2.2 External
Contacts
Description
(ID4 Through
ID8) (Cont’d)
Opened
Closed
Opened
Closed
See Damper Control Options for details.
Closed
Opened
Closed
Closed
1. Fan Auto Starts
2. Space Heating
3. DAT Stpt = 90°F
Active Sequence
Dampers
Heating
Contact
(ID6)
Active Fan
Control
Sequence
Fan = OFF
Fan
Contract
(ID5)
Alarm
Occ/Unocc
Contact
(ID4)
Unit Test
Mode
Thermostat or DDC
Contact Inputs
Dehumification
Contact
(ID8)
1. Fan Auto Starts
2. Space Cooling
3. DAT Stpt = 55°F
Active Sequence
Dampers
Cooling
Contact
(ID7)
Occupied
Mode
Dampers
Reheat Pump
OFF or Auto
Sequence
Auto
Sequence
Both True
Heating = Open
Cooling = Open
Dehumidification
= Open Fan Contact =
Open
All Mechanical
Equipment is OFF
MAT < 65°F
Follow Neutral Air
Heating Setpoint
Neutral Air Dehumidification
OA Dew Point > 58°F
MAT > 65°F
Follow Neutral Air
Cooling Setpoint
Fan Contact =
Closed
Unit Operation
Enable
ON
Enable
OFF
1. Fan Auto Starts
2. Space Dehum
3. DAT Stpt = 70°F
Active Sequence
Dampers
Opened
User has
pseudo
manual
control of all
mechanical
operation
Tab : Function
Set Fan
Speed
Unoccupied
Mode
Dampers
Enable OFF /

Form CP-MAPSIII-D19, Doc No 303069, Page 6
3.1 Supply Fan
Control
Uponacallforthesupplyfan,thesupplyfanwillstart.Iftheunitisconguredwitha
100% outside air damper, the damper actuator is electrically interlocked such that the
supply fan cannot start until the damper is 80% open.
When the Supply fan is commanded off, any active heating or cooling operation will be
shut down and the supply fan will stop after an adjustable time delay.
Whenthesupplyfan,cooling,heatinganddehumidicationcontactsareopenthesupply
fan is OFF. No other functions can automatically turn the fan ON except test mode.
A 30-second acceleration and deceleration rate for the supply fan to ramp between the
minimum and maximum motor frequency is factory set via the unit variable frequency
drive.
The supply fan will operate in one of the following six conditions.
1. High - Low Fan Speed Control (VFC1)
The variable frequency drive is commanded ON from NO1. There are two fan
speed states - active heating/cooling and fan only. When the fan is ON and the
heating or cooling contacts are closed, the unit will operate to high fan speed.
When the fan is ON and the cooling or heating contacts are open, the supply fan
will operate on low fan speed.
2. Duct Static Pressure Control (0.0” to 2.5” iwc) (Option VFC3)
The variable frequency drive is commanded ON from NO1. The fan modulates
between the user adjustable minimum and maximum fan speed setpoints using a
PI loop to maintain the duct static pressure setpoint (+0.5”w.c. default).
3. Summer/Winter Constant Volume (Option VFC9)
The variable frequency drive is commanded ON from NO1. The unit ramps up to
a user set supply fan speed setting. There are two individual supply fan speed
% setpoints one for heating and one for cooling. When the unit is in Space or
Neutral Air Heating, the supply fan will use the heating speed % setpoint. When
the unit is in any other mode, the supply fan will use cooling speed % setpoint.
The intake dampers operate based upon state, mode, and one of six user selected
sequences. The dampers are normally open and operational in the occupied mode and
closed to outside air in the unoccupied mode, depending on the user selection.
1. 100% OA, (Option GF2A)
When the unit is to start, the outside air damper will modulate (point Y1 =
10Vdc) and the supply fan will be commanded ON (point NO1 = On). If the
unit is equipped with an outside air damper, the damper actuator is electrically
interlocked to the fan start/stop such that the supply fan cannot start until the
damper is 80% open. Options AR8, AR2D, AR2L, and AR2Y are electrically
interlocked with the supply fan.
OFF and Alarm Modes
The damper will be closed (Y1 = 0%).
2. External 0-10vdc Input, (Option GF1)
Occupied & Unoccupied Mode
The dampers will modulate from 0-100% (point Y1 = 0 to 10 Vdc) based user
supplied 0 - 10 Vdc input. 0 Volts input is 0% damper while 10V input is 100%
damper position. This is not allowed with Options AR8, AR2D, AR2L & AR2Y. The
software does not prevent the selection of this option. The fan status switch will
handletheblockowcondition.ThedamperisNOTelectricallyinterlockedwith
the supply fan.
Unoccupied OFF and Alarm Modes
The damper will be closed (Y1 = 0%).
NOTE: For unoccupied operation of this damper control option, set the unoccupied
ventilation enable variable to ON
3.0 Controls
3.2 Intake Damper
Control

Form CP-MAPSIII-D19, Doc No 303069, Page 7
3. Two Position Dampers (Option GF2)
Occupied Mode
The damper will open to the user adjustable occupied damper position setpoint
value (point Y1 = 100%). For the damper options with only 100% outside air, the
mechanical interlock of 80% will not allow the fan to start. Adjust the outside air
setpoint to reach the minimum electrical interlock position.
Unoccupied Mode
With the unoccupied ventilation enable variable set to ON, the damper will open to
the user adjustable unoccupied damper position setpoint value (point Y1=0Vdc).
For the damper options with only 100% outside air, the mechanical interlock of
80% will not allow the fan to start. Adjust the outside air setpoint to reach the
minimum electrical interlock position. With the unoccupied ventilation enable
variable set to off the damper will be commanded to 0%.
OFF and Alarm Modes
The damper will be closed (Y1 = 0%).
4. Four Positions based on 2 Digital Inputs (Option GF4)
Occupied Mode
Thedamperwillopentotheuseradjustabledenedpositionbasedupontwo
hardware input switches (ID9 & ID10).
Variable
Name
Input Switch Default Dmpr
Position
Display
Range
Y1 Output
Range
ID9 ID10
Aux_1_SP Open Open 20% 0-100% 0 – 10V
Aux_2_SP Close Open 40% 0-100% 0 – 10V
Aux_3_SP Open Close 60% 0-100% 0 – 10V
Aux_4_SP Close Close 80% 0-100% 0 – 10V
This option is not allowed with AR8, AR2D, AR2L, and AR2Y. The software does
not prevent the selection of this option. The fan status switch will handle the block
owcondition.
Unoccupied, OFF and Alarm Modes
The damper will be closed (Y1 = 0%).
5. Economizer Package (Option GF8)
Occupied Mode
The dampers will modulate to the user adjustable minimum position setting when
the unit is in occupied mode (MinDmprSP, Default = 10%). When the CO2sensor
option is selected (input U9), the minimum damper position will be determined as
follows: If the Space CO2level exceeds the (SpcCO2SP, default = 1000 ppm)
with a 200 ppm differential (SpcCO2Diff, default = 200 ppm), the user adjustable
(CO2DmprOsSP, Default = 10%) value will be added to the (MinDmprSP, Default
= 10%)
CO2> 1000 ppm = Active Minimum Damper Position 20%
CO2< 800 ppm = Active Minimum Damper Position 10%
When cooling is required via the thermostat input ID7 and the outdoor air
temperature is less than the economizer temperature lockout and the economizer
dewpoint lockout, the dampers will modulate using a PID from the minimum
position to the maximum position to maintain the mixed air temperature at the
DA_SpcClg_SP.
When cooling is required via Auto Sequence Cool and the outdoor air temperature
is less than the economizer temperature lockout and the economizer dewpoint
lockout, the dampers will modulate using a PID from the minimum position to the
maximum position to maintain the mixed air temperature at the DA_NAClg_SP.
When cooling is not required, the dampers will revert to the minimum position.
Unoccupied, OFF and Alarm Modes
The damper will be closed (Y1 = 0%).

Form CP-MAPSIII-D19, Doc No 303069, Page 8
6.Building Pressure Control (Range -0.5 to 0.5”iwc) (Option GF5)
Occupied Mode
The dampers will modulate using a PI loop to maintain the building static pressure
setpoint, default 0.1” iwc Y1 will modulate from 0-100% open, 0-10V.
Unoccupied, OFF and Alarm Modes - The damper will be closed (Y1 = 0%).
The unit is inherently a discharge air temperature control system. The unit will
operate to maintain one of the following discharge air setpoints depending on the
state and mode. All setpoints are user adjustable from the unit display and the wall
mounted user interface.
The unit switches setpoints based upon states, mode, and space control requirements.
Heating Setpoint Selection
The unit will automatically switch between the two setpoints based on the following:
Unit Discharge Setpoints
# State Discharge Air
Control Variable Default Septoint Range
1Auto Sequence
Heat
Neutral Air
Temperature DA_NAHtg_SP 65°F (18.3°C)
50 -120°F
(10 - 48.9°C)
2Heating
Contacts
Space Heating Air
Temperature DA_SpcHtg_SP 90°F (32.2°C)
50 -140°F
(10 - 60°C)
Sliding Scale: Neutral Air Heating Temperature Reset Schedule Setpoint
The user can also select a reset schedule for the discharge setpoint used when in
neutral air heating mode.
Reset Schedule
Outside Air
Temperature
Discharge Air
Temperature
30°F
(-1.1°C)
75°F
(23.8°C)
65°F
(18.3°C)
65°F
(18.3°C)
Sliding Scale: Space Heating Temperature Reset Schedule Setpoint
The user can also select a reset schedule for the discharge setpoint used when in
space heating mode.
Reset Schedule
Outside Air
Temperature
Discharge Air
Temperature
30°F
(-1.1°C)
120°F
(48.9°C)
65°F
(18.3°C)
90°F
(32.2°C)
3.2 Intake Damper
Control (cont’d)
3.3 Temperature
And Humidity
Control

Form CP-MAPSIII-D19, Doc No 303069, Page 9
3.4.1 Electric Heat Staging
A call for heat will occur when the discharge air temperature is 5°F(2.8°C) below
the active setpoint. When the OAT is below 60°F/16°C (Heating Lockout SP), the
unit enables the electric heat to maintain the active setpoint. The unit will stage as
shown in the staging chart and the PI loop will activate. Stages should be assumed
cumulative from the previous stage.
Electric Heat Staging
PI Loop Control: All Statements Must Be True To Activate or De-Activate.
All stages will have an adjustable min ON and OFF time.
Stage Outputs
Increase
Inter-Stg
Timer
Activate
Decrease
Inter-Stg
Timer
De-activate
Stg 1 NO8 = ON DAT 5°F (2.8°C) below setpoint
(Y3 Modulates via Heating Demand) 15 min Heating Demand < 2.5% & DAT 5°F (2.8°C) above setpoint
Stg 2 NO9 = ON 10 min Heating Demand > 70% & DAT
5°F(2.8°C) below setpoint 2 min Heating Demand < 5% & DAT 5°F(2.8°C) above setpoint
Stg 3 NO10 = ON 10 min Heating Demand > 75% & DAT
5°F(2.8°C) below setpoint 2 min Heating Demand < 10% & DAT 5°F(2.8°C) above setpoint
Stg 4 NO11 = ON 10 min Heating Demand > 80% & DAT
5°F(2.8°C) below setpoint 2 min Heating Demand < 20% & DAT 5°F(2.8°C) above setpoint
Stg 5 NO12 = ON 10 min Heating Demand > 85% & DAT
5°F(2.8°C) below setpoint 2 min Heating Demand < 30% & DAT 5°F(2.8°C) above setpoint
Stg 6 NO13 = ON 10 min Heating Demand > 90% & DAT
5°F(2.8°C) below setpoint 2 min Heating Demand < 40% & DAT 5°F(2.8°C) above setpoint
All parameters are factory level access.
3.4.2 Gas Heat Staging
A call for heat will occur when the discharge air temperature is 5°F(2.8°C) below
the active setpoint. When the OAT is below 60°F/16°C (Heating Lockout SP), the
unit enables the gas heat to maintain the active setpoint. The unit will stage and
modulate as shown in the staging chart and the PI loop will activate. Stages should
be assumed cumulative from the previous stage.
Gas Heat Staging
PI Loop Control: All Statements Must Be True To Activate or De-Activate.
All stages will have an adjustable min ON and OFF time.
Stage Outputs
Increase
Inter-Stg
Timer
Activate
Decrease
Inter-Stg
Timer
De-activate
Stg 1
Y3 = 24% for
30 seconds
& NO8 = ON
DAT 5°F (2.8°C) below setpoint
(Y3 Modulates Heat Exchanger 1
via Heating Demand)
15 min Heating Demand < 2.5% & DAT
5°F (2.8°C) above setpoint
Stg 2
Y4 = 24% for
30 seconds
NO9 = ON
10 min
Heating Demand > 50% (Y3
Heat Exhanger 1 = 100%) & DAT
5°F(2.8°C) below setpoint (Y4
Modulates Heat Exchanger 2 via
Heating Demand)
15 min Heating Demand < 25% & DAT
5°F(2.8°C) above setpoint
All parameters are factory level access.
Heat Exchanger 1 Heat Exchanger 2
0% 100%
Output Y3
Heating Demand
100%
10 Vdc
Output Y4
0%
2 Vdc
100%
10 Vdc
0%
2 Vdc
50%
3.4 Heating Control

Form CP-MAPSIII-D19, Doc No 303069, Page 10
3.0 Controls
(Cont’d)
The unit will switch between the setpoints based on the following:
Unit Discharge Setpoints
# State Occ /
Unocc
Discharge Air
Control Variable Default Septoint Range
1Auto Sequence
Cooling Occ Neutral Air Temperature DA_NAClg_SP 75°F (24°C)
50 - 100°F
(10 - 37°C)
2Cooling
Contacts Occ Space Cooling Air Temperature DA_SpcClg_SP 55°F (12°C)
50 -100°F
(10 - 37°C)
A call for mechanical cooling will occur when the discharge air temperature is 5°F
(2.8°C) above the active setpoint. When the OAT is above 60°F/16°C (Cooling
Lockout SP), the unit enables the mechanical cooling to maintain the active setpoint.
Cooling capacity/staging will follow a PI loop to maintain the active setpoint. Space
Cooling Active = Space dehumidication Y5 Reheat_Mod_Capacity and NO17 Reheat
Compressor Command not permitted.
DX Mechanical Cooling Staging
PI Loop Control: All Statements Must Be True To Activate or De-Activate
All stages will have an adjustable min ON and OFF time
Stage Output Increase
Stage Timing Activate Decrease Stage Timing De-activate
Stg 1 NO2 5 min DAT 5°F(2.8°C) above setpoint 5 min Cooling Demand < 10 % & DAT
5°F(2.8°C) below setpoint
Stg 2 NO3 5 min Cooling Demand > 70% & DAT
5°F(2.8°C) above setpoint 5 min Cooling Demand < 50% & DAT 5°F(2.8°C) below setpoint
Stg 3 NO4 5 min Cooling Demand > 80% & DAT
5°F(2.8°C) above setpoint 5 min Cooling Demand < 55% & DAT 5°F(2.8°C) below setpoint
Stg 4 NO5 5 min Cooling Demand > 90% & DAT
5°F(2.8°C) above setpoint 5 min Cooling Demand < 60% & DAT 5°F(2.8°C) below setpoint
All parameters are factory level access.
Dehumidication Commands
Thereisacallfordehumidicationifoneofthefollowingistrue.
1. SpaceDehumidicactionMode-Thedehumcontactisclosed.
2. NeutralAirDehumidicationMode-Theoutdoorairdewpointisabovethedew
point setpoint. (58°F/14°C) and the unit is in auto sequence cooling or heating.
When either the space dehumidication mode or the neutral air dehumidication
mode are active, the main evaporator compressor(s) will be enabled to maintain a
52°F(11°C) cooling coil discharge setpoint and will use the U5 CC_Temp sensor. The
reheat compressor and the reheat valve output Y5 will be enabled to modulate to
maintain the reheat setpoint 70°F(21°C) via the U4 DAT temp sensor.
Any of the following conditions will lockout the space dehumidication Mode:
1. The outdoor air temperature is below the reheat lockout setpoint, (58°F/14°C,
reheat lockout, range 50-100°F/10-37°C) Drybulb.
2. The outdoor air temperature is above the reheat high lockout setpoint.
(100°F/37°C, reheat high lockout, range 50-120°F/10-48°C) Drybulb
3. The space cooling mode is active.
4. Cooling Coil Sensor failure.
Any of the following conditions will lockout the neutral air dehumidication Mode:
1. The outdoor air temperature is below the reheat lockout setpoint, (58°F/14°C,
reheat lockout, range 50-100°F/10-37°C) Drybulb
2. The outdoor air temperature is above the reheat high lockout setpoint.
(100°F/37°C), reheat high lockout, range 50-120°F/10-48°C) Drybulb
3. Outside Air Humidity Sensor or Cooling Coil Sensor failure.
4. OA dewpoint less than 58°F(14°C).
3.5 Cooling Control
3.6 Dehumidication