Reznor RCB User Manual

Form CP-MAPSIII-D21, Doc No 303070, Page 7
Manual Heating
State
Mode
Occ or Unocc
Unit OFF
State
Control System Unit State, Mode, Major DAT Septoint
Manual Cooling
State
Off / Alarm
State
Unit Test
Mode
Fan = OFF
Mode
Occ or Unocc
Auto Heat / Cool
State
Outside Air
Temp >65°F
(18°C)
Fan = OFF
Fan = Intermittent
See Note 1.
Fan = ON and
Speed = to Maximum
Speed Setpoint
Fan = ON
Fan = ON
Occ Mode
Unocc Mode
Unocc Mode
Occ Mode
Fan = Intermittent
See Note 1.
No Yes
State
Mode
Fan
Function
NOTE 1. - Intermittent operation of the supply fan will be based on an increased space cooling setpoint and
a decreased space heating setpoint during the unoccupied mode.
Supply Fan Control:
Occupied Mode
When the unit is called to be in occupied mode, the supply fan will start. If the unit is
conguredwitha100%outsideairdamper,thedamperactuatoriselectricallyinter-
locked 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 operations will
be shut down and the supply fan will stop after an adjustable time delay.
The rate is controlled by unit state, mode and the selection of one of the following
sequences of operation:
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 system is in either the space
heating or space cooling mode, the unit will operate on high fan speed. When
the fan is ON and the system is not in either the space cooling or space heating
mode, 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”iwc default.
3. Building Static Pressure Control (-0.5” to 0.5” iwc) (Option VFC4) 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 building static pressure setpoint, +0.1”iwc default.
4. 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.
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.
Supply Fan Control : Unoccupied Mode
Whenconguredforspacecontrol,thesupplyfanoperationwillbeintermittentbased
on the zone temperature. See Temperature and Humidity Control section, Paragraph
3.7,forspacecontrolandsetpointdenitions.

Reznor RCB Specifications

General

Brand	Reznor
Model	RCB
Category	Air Handlers
Language	English