Reznor RCB User Manual

Form CP-MAPSIII-D21, Doc No 303070, Page 9
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. Selected setpoints are user adjustable from the unit display and the
wall mounted user interface.
Discharge Air Temperature (DAT) Setpoint Decision Tree
Space Temperature Control Req’d
Initiate: Space Temp 4°F(2.1°C) > SpcEffClgSP
Release: Space Temp 1°F(.4°C) < SpcEffClgSP
DAT Setpoint = 55°F(12°C); 50-100°F(10-37°C)
Space Humidity Control Req’d
Initiate: Space %RH 10% > Setpoint
Release: Space %RH 5% < Setpoint
Space %RH Setpoint = 55%; 35-75%
DAT Sp = 70°F(21°C); 50-100°F(10-37°C)
Main Coil Setpoint CC-T = 52°F(11°C)
Required
State
•Heat
•Cool
•Auto
(Unit cycles ON based on Space Temperature
Control.)
DAT Setpoint = 90°F(32°C); 50-100°F(10-37°C)
Space
Heating
Required
HEATING
Space
Cooling
Required
Neutral Air Temperature Control
DAT Sp = 70°F(21°C); 50-100°F(10-37°C)
COOLING
Space Temperature Control Req’d
Initiate: Space Temp 4°F(2.1°C) > SpcEffClgSP
Release: Space Temp 1°F(.4°C) < SpcEffClgSP
DAT Setpoint = 55°F(12°C); 50-100°F
(10-37°C)
(Unit Cycles ON based on
Space Temperature Control.)
Occ
Mode
Unocc
Mode
Space
Dehumidification
Required
Occ
Mode
Unocc
Mode
Space
Cooling
Required
Initiate: Space Temp 5°F(2.8°C) > SpcHtgSP
Release: Space Temp 1°F(.4°C) < SpcHtgSP
DAT Setpoint = 55°F(12°C); 50-100°F (10-37°C)
(Auto Heating Only)
Occ
Mode
Unocc
Mode
Occ
Mode
Unocc
Mode
YES
YES
YES
YES
Unit Off
NO
NO
Occ
Mode
Unocc
Mode
Neutral Air Dehumidification Control
Req’d Dehum OAT Dewpoint > 58°F(14°C);
48-90°F(8-32°C)
DAT Setpoint = 70°F(21°C);
50-100°F(10-37°C)
Main Coil Setpoint CC-T = 52°F(11°C)
Neutral Air Temperature Control
Neutral Air
Dehum
Req’d
NO
Unit Off
YES
NO
NO
* If the space temperature sensor (th-Tune) is not enabled or fails,
the logic will ignore the space requirements and operate to maintain
neutral air temperature and neutral air dehumidification control. If the
th-Tune is enabled and fails, an alarm condition is created.
Occ
Mode
Unocc
Mode
Space Humidity Control Req’d
Initiate: Space %RH 10% > Setpoint
Release: Space %RH 5% < Setpoint
Space %RH Setpoint = 55%; 35-75%
DAT Sp = 70°F(21°C); 50-100°F(10-37°C)
(Unit cycles on based upon Space
Dehumidification Control.)
Main Coil Setpoint CC-T = 52°F(11°C)
DAT Setpoint = 70°F(21°C);
50-100°F(10-37°C)
Space Temperature Control Req’d
Initiate: Space Temp 4°F(2.1°C) > SpcEffHtgSP
Release: Space Temp 1°F(.4°C) < SpcEffHtgSP
DAT Setpoint = 90°F(32°C); 50-100°F(10-37°C)
Space Temperature Control Req’d
Initiate: Space Temp 4°F(2.1°C) > SpcEffHtgSP
Release: Space Temp 1°F(.4°C) < SpcEffHtgSP
Space Temperature Control Req’d
Or Sliding Scale
Unit Off
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: Temperature Reset Schedule Setpoint (heating Only)
The user can also select a reset schedule for the discharge setpoint used when in
neutral air heating mode.
3.3 Temperature
And Humidity
Control

Reznor RCB Specifications

General

Brand	Reznor
Model	RCB
Category	Air Handlers
Language	English